Even / Odd Numbers - PSAT Math
Card 1 of 231
You are given that
,
, and
are positive integers, and

In which of the following cases is
odd?
I) Exactly one of
is odd.
II) Exactly two of
are odd.
III) Exactly three of
are odd.
You are given that ,
, and
are positive integers, and
In which of the following cases is odd?
I) Exactly one of is odd.
II) Exactly two of are odd.
III) Exactly three of are odd.
Tap to reveal answer
For the product of three integers to be odd, all three integers must themselves be odd.
At least two of
must have the same odd/even status. The sum of those two numbers must be even, and since it is a factor of
, then
itself must be even.
For the product of three integers to be odd, all three integers must themselves be odd.
At least two of must have the same odd/even status. The sum of those two numbers must be even, and since it is a factor of
, then
itself must be even.
← Didn't Know|Knew It →
You are given that
,
, and
are positive integers, and

In which of the following cases is
odd?
I) Exactly one of
is odd.
II) Exactly two of
are odd.
III) Exactly three of
are odd.
You are given that ,
, and
are positive integers, and
In which of the following cases is odd?
I) Exactly one of is odd.
II) Exactly two of are odd.
III) Exactly three of are odd.
Tap to reveal answer
For the product of three integers to be odd, all three integers must themselves be odd.
At least two of
must have the same odd/even status. The sum of those two numbers must be even, and since it is a factor of
, then
itself must be even.
For the product of three integers to be odd, all three integers must themselves be odd.
At least two of must have the same odd/even status. The sum of those two numbers must be even, and since it is a factor of
, then
itself must be even.
← Didn't Know|Knew It →
You are given that
,
, and
are positive integers, and

In which of the following cases is
odd?
I) Exactly one of
is odd.
II) Exactly two of
are odd.
III) Exactly three of
are odd.
You are given that ,
, and
are positive integers, and
In which of the following cases is odd?
I) Exactly one of is odd.
II) Exactly two of are odd.
III) Exactly three of are odd.
Tap to reveal answer
For the product of three integers to be odd, all three integers must themselves be odd.
At least two of
must have the same odd/even status. The sum of those two numbers must be even, and since it is a factor of
, then
itself must be even.
For the product of three integers to be odd, all three integers must themselves be odd.
At least two of must have the same odd/even status. The sum of those two numbers must be even, and since it is a factor of
, then
itself must be even.
← Didn't Know|Knew It →
You are given that
,
, and
are positive integers, and
is odd.
Which of the following is possible?
I) Exactly one of
is odd.
II) Exactly two of
are odd.
III) Exactly three of
are odd.
You are given that ,
, and
are positive integers, and
is odd.
Which of the following is possible?
I) Exactly one of is odd.
II) Exactly two of are odd.
III) Exactly three of are odd.
Tap to reveal answer
For the product of three integers to be odd, all three integers must themselves be odd.
must be even, so for
to be odd,
must be odd. Similarly, for
and
to be odd, respectively,
and
must be odd.
Therefore, all three of
,
, and
must be odd, and the correct response is III only.
For the product of three integers to be odd, all three integers must themselves be odd.
must be even, so for
to be odd,
must be odd. Similarly, for
and
to be odd, respectively,
and
must be odd.
Therefore, all three of ,
, and
must be odd, and the correct response is III only.
← Didn't Know|Knew It →
You are given that
,
, and
are positive integers, and

In which of the following cases is
odd?
I) Exactly one of
is odd.
II) Exactly two of
are odd.
III) Exactly three of
are odd.
You are given that ,
, and
are positive integers, and
In which of the following cases is odd?
I) Exactly one of is odd.
II) Exactly two of are odd.
III) Exactly three of are odd.
Tap to reveal answer
For the product of three integers to be odd, all three integers must themselves be odd.
At least two of
must have the same odd/even status. The sum of those two numbers must be even, and since it is a factor of
, then
itself must be even.
For the product of three integers to be odd, all three integers must themselves be odd.
At least two of must have the same odd/even status. The sum of those two numbers must be even, and since it is a factor of
, then
itself must be even.
← Didn't Know|Knew It →
You are given that
,
, and
are positive integers, and

In which of the following cases is
odd?
I) Exactly one of
is odd.
II) Exactly two of
are odd.
III) Exactly three of
are odd.
You are given that ,
, and
are positive integers, and
In which of the following cases is odd?
I) Exactly one of is odd.
II) Exactly two of are odd.
III) Exactly three of are odd.
Tap to reveal answer
For the product of three integers to be odd, all three integers must themselves be odd.
At least two of
must have the same odd/even status. The sum of those two numbers must be even, and since it is a factor of
, then
itself must be even.
For the product of three integers to be odd, all three integers must themselves be odd.
At least two of must have the same odd/even status. The sum of those two numbers must be even, and since it is a factor of
, then
itself must be even.
← Didn't Know|Knew It →
You are given that
,
, and
are positive integers, and
is odd.
Which of the following is possible?
I) Exactly one of
is odd.
II) Exactly two of
are odd.
III) Exactly three of
are odd.
You are given that ,
, and
are positive integers, and
is odd.
Which of the following is possible?
I) Exactly one of is odd.
II) Exactly two of are odd.
III) Exactly three of are odd.
Tap to reveal answer
For the product of three integers to be odd, all three integers must themselves be odd.
must be even, so for
to be odd,
must be odd. Similarly, for
and
to be odd, respectively,
and
must be odd.
Therefore, all three of
,
, and
must be odd, and the correct response is III only.
For the product of three integers to be odd, all three integers must themselves be odd.
must be even, so for
to be odd,
must be odd. Similarly, for
and
to be odd, respectively,
and
must be odd.
Therefore, all three of ,
, and
must be odd, and the correct response is III only.
← Didn't Know|Knew It →
You are given that
,
, and
are positive integers, and

In which of the following cases is
odd?
I) Exactly one of
is odd.
II) Exactly two of
are odd.
III) Exactly three of
are odd.
You are given that ,
, and
are positive integers, and
In which of the following cases is odd?
I) Exactly one of is odd.
II) Exactly two of are odd.
III) Exactly three of are odd.
Tap to reveal answer
For the product of three integers to be odd, all three integers must themselves be odd.
At least two of
must have the same odd/even status. The sum of those two numbers must be even, and since it is a factor of
, then
itself must be even.
For the product of three integers to be odd, all three integers must themselves be odd.
At least two of must have the same odd/even status. The sum of those two numbers must be even, and since it is a factor of
, then
itself must be even.
← Didn't Know|Knew It →
You are given that
,
, and
are positive integers, and
is odd.
Which of the following is possible?
I) Exactly one of
is odd.
II) Exactly two of
are odd.
III) Exactly three of
are odd.
You are given that ,
, and
are positive integers, and
is odd.
Which of the following is possible?
I) Exactly one of is odd.
II) Exactly two of are odd.
III) Exactly three of are odd.
Tap to reveal answer
For the product of three integers to be odd, all three integers must themselves be odd.
must be even, so for
to be odd,
must be odd. Similarly, for
and
to be odd, respectively,
and
must be odd.
Therefore, all three of
,
, and
must be odd, and the correct response is III only.
For the product of three integers to be odd, all three integers must themselves be odd.
must be even, so for
to be odd,
must be odd. Similarly, for
and
to be odd, respectively,
and
must be odd.
Therefore, all three of ,
, and
must be odd, and the correct response is III only.
← Didn't Know|Knew It →
You are given that
,
, and
are positive integers, and
is odd.
Which of the following is possible?
I) Exactly one of
is odd.
II) Exactly two of
are odd.
III) Exactly three of
are odd.
You are given that ,
, and
are positive integers, and
is odd.
Which of the following is possible?
I) Exactly one of is odd.
II) Exactly two of are odd.
III) Exactly three of are odd.
Tap to reveal answer
For the product of three integers to be odd, all three integers must themselves be odd.
must be even, so for
to be odd,
must be odd. Similarly, for
and
to be odd, respectively,
and
must be odd.
Therefore, all three of
,
, and
must be odd, and the correct response is III only.
For the product of three integers to be odd, all three integers must themselves be odd.
must be even, so for
to be odd,
must be odd. Similarly, for
and
to be odd, respectively,
and
must be odd.
Therefore, all three of ,
, and
must be odd, and the correct response is III only.
← Didn't Know|Knew It →
You are given that
,
, and
are positive integers, and

In which of the following cases is
odd?
I) Exactly one of
is odd.
II) Exactly two of
are odd.
III) Exactly three of
are odd.
You are given that ,
, and
are positive integers, and
In which of the following cases is odd?
I) Exactly one of is odd.
II) Exactly two of are odd.
III) Exactly three of are odd.
Tap to reveal answer
For the product of three integers to be odd, all three integers must themselves be odd.
At least two of
must have the same odd/even status. The sum of those two numbers must be even, and since it is a factor of
, then
itself must be even.
For the product of three integers to be odd, all three integers must themselves be odd.
At least two of must have the same odd/even status. The sum of those two numbers must be even, and since it is a factor of
, then
itself must be even.
← Didn't Know|Knew It →
You are given that
,
, and
are positive integers, and
is odd.
Which of the following is possible?
I) Exactly one of
is odd.
II) Exactly two of
are odd.
III) Exactly three of
are odd.
You are given that ,
, and
are positive integers, and
is odd.
Which of the following is possible?
I) Exactly one of is odd.
II) Exactly two of are odd.
III) Exactly three of are odd.
Tap to reveal answer
For the product of three integers to be odd, all three integers must themselves be odd.
must be even, so for
to be odd,
must be odd. Similarly, for
and
to be odd, respectively,
and
must be odd.
Therefore, all three of
,
, and
must be odd, and the correct response is III only.
For the product of three integers to be odd, all three integers must themselves be odd.
must be even, so for
to be odd,
must be odd. Similarly, for
and
to be odd, respectively,
and
must be odd.
Therefore, all three of ,
, and
must be odd, and the correct response is III only.
← Didn't Know|Knew It →
You are given that
,
, and
are positive integers, and
is odd.
Which of the following is possible?
I) Exactly one of
is odd.
II) Exactly two of
are odd.
III) Exactly three of
are odd.
You are given that ,
, and
are positive integers, and
is odd.
Which of the following is possible?
I) Exactly one of is odd.
II) Exactly two of are odd.
III) Exactly three of are odd.
Tap to reveal answer
For the product of three integers to be odd, all three integers must themselves be odd.
must be even, so for
to be odd,
must be odd. Similarly, for
and
to be odd, respectively,
and
must be odd.
Therefore, all three of
,
, and
must be odd, and the correct response is III only.
For the product of three integers to be odd, all three integers must themselves be odd.
must be even, so for
to be odd,
must be odd. Similarly, for
and
to be odd, respectively,
and
must be odd.
Therefore, all three of ,
, and
must be odd, and the correct response is III only.
← Didn't Know|Knew It →
You are given that
,
, and
are positive integers, and
is odd.
Which of the following is possible?
I) Exactly one of
is odd.
II) Exactly two of
are odd.
III) Exactly three of
are odd.
You are given that ,
, and
are positive integers, and
is odd.
Which of the following is possible?
I) Exactly one of is odd.
II) Exactly two of are odd.
III) Exactly three of are odd.
Tap to reveal answer
For the product of three integers to be odd, all three integers must themselves be odd.
must be even, so for
to be odd,
must be odd. Similarly, for
and
to be odd, respectively,
and
must be odd.
Therefore, all three of
,
, and
must be odd, and the correct response is III only.
For the product of three integers to be odd, all three integers must themselves be odd.
must be even, so for
to be odd,
must be odd. Similarly, for
and
to be odd, respectively,
and
must be odd.
Therefore, all three of ,
, and
must be odd, and the correct response is III only.
← Didn't Know|Knew It →
,
,
, and
are positive integers.
is odd.
Which of the following is possible?
I) Exactly two of
are odd.
II) Exactly three of
are odd.
III) All four of
are odd.
,
,
, and
are positive integers.
is odd.
Which of the following is possible?
I) Exactly two of are odd.
II) Exactly three of are odd.
III) All four of are odd.
Tap to reveal answer
If exactly two of
are odd, then exactly one of the seven expressions being added is odd - namely, the only one that does not have an even factor (for example, if
and
are odd, then the only odd number is
). This makes
the sum of one odd number and six even number and, subsequently, odd.
If exactly three of
are odd, then exactly three of the seven expressions being added are odd - namely, the three that do not include the even factor (for example, if
,
, and
are odd, then the three odd numbers are
,
, and
). This makes
the sum of three odd numbers and four even numbers and, subsequently, odd.
If all four of
are odd, then all of the seven expressions being added, being the product of only odd numbers, are odd. This makes
the sum of seven odd numbers, and, subsequently, odd.
The correct choice is that all three scenarios are possible.
If exactly two of are odd, then exactly one of the seven expressions being added is odd - namely, the only one that does not have an even factor (for example, if
and
are odd, then the only odd number is
). This makes
the sum of one odd number and six even number and, subsequently, odd.
If exactly three of are odd, then exactly three of the seven expressions being added are odd - namely, the three that do not include the even factor (for example, if
,
, and
are odd, then the three odd numbers are
,
, and
). This makes
the sum of three odd numbers and four even numbers and, subsequently, odd.
If all four of are odd, then all of the seven expressions being added, being the product of only odd numbers, are odd. This makes
the sum of seven odd numbers, and, subsequently, odd.
The correct choice is that all three scenarios are possible.
← Didn't Know|Knew It →
,
,
, and
are positive integers.
is odd.
Which of the following is possible?
I) Exactly two of
are odd.
II) Exactly three of
are odd.
III) All four of
are odd.
,
,
, and
are positive integers.
is odd.
Which of the following is possible?
I) Exactly two of are odd.
II) Exactly three of are odd.
III) All four of are odd.
Tap to reveal answer
If exactly two of
are odd, then exactly one of the seven expressions being added is odd - namely, the only one that does not have an even factor (for example, if
and
are odd, then the only odd number is
). This makes
the sum of one odd number and six even number and, subsequently, odd.
If exactly three of
are odd, then exactly three of the seven expressions being added are odd - namely, the three that do not include the even factor (for example, if
,
, and
are odd, then the three odd numbers are
,
, and
). This makes
the sum of three odd numbers and four even numbers and, subsequently, odd.
If all four of
are odd, then all of the seven expressions being added, being the product of only odd numbers, are odd. This makes
the sum of seven odd numbers, and, subsequently, odd.
The correct choice is that all three scenarios are possible.
If exactly two of are odd, then exactly one of the seven expressions being added is odd - namely, the only one that does not have an even factor (for example, if
and
are odd, then the only odd number is
). This makes
the sum of one odd number and six even number and, subsequently, odd.
If exactly three of are odd, then exactly three of the seven expressions being added are odd - namely, the three that do not include the even factor (for example, if
,
, and
are odd, then the three odd numbers are
,
, and
). This makes
the sum of three odd numbers and four even numbers and, subsequently, odd.
If all four of are odd, then all of the seven expressions being added, being the product of only odd numbers, are odd. This makes
the sum of seven odd numbers, and, subsequently, odd.
The correct choice is that all three scenarios are possible.
← Didn't Know|Knew It →
,
,
, and
are positive integers.
is odd.
Which of the following is possible?
I) Exactly two of
are odd.
II) Exactly three of
are odd.
III) All four of
are odd.
,
,
, and
are positive integers.
is odd.
Which of the following is possible?
I) Exactly two of are odd.
II) Exactly three of are odd.
III) All four of are odd.
Tap to reveal answer
If exactly two of
are odd, then exactly one of the seven expressions being added is odd - namely, the only one that does not have an even factor (for example, if
and
are odd, then the only odd number is
). This makes
the sum of one odd number and six even number and, subsequently, odd.
If exactly three of
are odd, then exactly three of the seven expressions being added are odd - namely, the three that do not include the even factor (for example, if
,
, and
are odd, then the three odd numbers are
,
, and
). This makes
the sum of three odd numbers and four even numbers and, subsequently, odd.
If all four of
are odd, then all of the seven expressions being added, being the product of only odd numbers, are odd. This makes
the sum of seven odd numbers, and, subsequently, odd.
The correct choice is that all three scenarios are possible.
If exactly two of are odd, then exactly one of the seven expressions being added is odd - namely, the only one that does not have an even factor (for example, if
and
are odd, then the only odd number is
). This makes
the sum of one odd number and six even number and, subsequently, odd.
If exactly three of are odd, then exactly three of the seven expressions being added are odd - namely, the three that do not include the even factor (for example, if
,
, and
are odd, then the three odd numbers are
,
, and
). This makes
the sum of three odd numbers and four even numbers and, subsequently, odd.
If all four of are odd, then all of the seven expressions being added, being the product of only odd numbers, are odd. This makes
the sum of seven odd numbers, and, subsequently, odd.
The correct choice is that all three scenarios are possible.
← Didn't Know|Knew It →
,
,
, and
are positive integers.
is odd.
Which of the following is possible?
I) Exactly two of
are odd.
II) Exactly three of
are odd.
III) All four of
are odd.
,
,
, and
are positive integers.
is odd.
Which of the following is possible?
I) Exactly two of are odd.
II) Exactly three of are odd.
III) All four of are odd.
Tap to reveal answer
If exactly two of
are odd, then exactly one of the seven expressions being added is odd - namely, the only one that does not have an even factor (for example, if
and
are odd, then the only odd number is
). This makes
the sum of one odd number and six even number and, subsequently, odd.
If exactly three of
are odd, then exactly three of the seven expressions being added are odd - namely, the three that do not include the even factor (for example, if
,
, and
are odd, then the three odd numbers are
,
, and
). This makes
the sum of three odd numbers and four even numbers and, subsequently, odd.
If all four of
are odd, then all of the seven expressions being added, being the product of only odd numbers, are odd. This makes
the sum of seven odd numbers, and, subsequently, odd.
The correct choice is that all three scenarios are possible.
If exactly two of are odd, then exactly one of the seven expressions being added is odd - namely, the only one that does not have an even factor (for example, if
and
are odd, then the only odd number is
). This makes
the sum of one odd number and six even number and, subsequently, odd.
If exactly three of are odd, then exactly three of the seven expressions being added are odd - namely, the three that do not include the even factor (for example, if
,
, and
are odd, then the three odd numbers are
,
, and
). This makes
the sum of three odd numbers and four even numbers and, subsequently, odd.
If all four of are odd, then all of the seven expressions being added, being the product of only odd numbers, are odd. This makes
the sum of seven odd numbers, and, subsequently, odd.
The correct choice is that all three scenarios are possible.
← Didn't Know|Knew It →
,
,
, and
are positive integers.
is odd.
Which of the following is possible?
I) Exactly two of
are odd.
II) Exactly three of
are odd.
III) All four of
are odd.
,
,
, and
are positive integers.
is odd.
Which of the following is possible?
I) Exactly two of are odd.
II) Exactly three of are odd.
III) All four of are odd.
Tap to reveal answer
If exactly two of
are odd, then exactly one of the seven expressions being added is odd - namely, the only one that does not have an even factor (for example, if
and
are odd, then the only odd number is
). This makes
the sum of one odd number and six even number and, subsequently, odd.
If exactly three of
are odd, then exactly three of the seven expressions being added are odd - namely, the three that do not include the even factor (for example, if
,
, and
are odd, then the three odd numbers are
,
, and
). This makes
the sum of three odd numbers and four even numbers and, subsequently, odd.
If all four of
are odd, then all of the seven expressions being added, being the product of only odd numbers, are odd. This makes
the sum of seven odd numbers, and, subsequently, odd.
The correct choice is that all three scenarios are possible.
If exactly two of are odd, then exactly one of the seven expressions being added is odd - namely, the only one that does not have an even factor (for example, if
and
are odd, then the only odd number is
). This makes
the sum of one odd number and six even number and, subsequently, odd.
If exactly three of are odd, then exactly three of the seven expressions being added are odd - namely, the three that do not include the even factor (for example, if
,
, and
are odd, then the three odd numbers are
,
, and
). This makes
the sum of three odd numbers and four even numbers and, subsequently, odd.
If all four of are odd, then all of the seven expressions being added, being the product of only odd numbers, are odd. This makes
the sum of seven odd numbers, and, subsequently, odd.
The correct choice is that all three scenarios are possible.
← Didn't Know|Knew It →
,
,
, and
are positive integers.
is odd.
Which of the following is possible?
I) Exactly two of
are odd.
II) Exactly three of
are odd.
III) All four of
are odd.
,
,
, and
are positive integers.
is odd.
Which of the following is possible?
I) Exactly two of are odd.
II) Exactly three of are odd.
III) All four of are odd.
Tap to reveal answer
If exactly two of
are odd, then exactly one of the seven expressions being added is odd - namely, the only one that does not have an even factor (for example, if
and
are odd, then the only odd number is
). This makes
the sum of one odd number and six even number and, subsequently, odd.
If exactly three of
are odd, then exactly three of the seven expressions being added are odd - namely, the three that do not include the even factor (for example, if
,
, and
are odd, then the three odd numbers are
,
, and
). This makes
the sum of three odd numbers and four even numbers and, subsequently, odd.
If all four of
are odd, then all of the seven expressions being added, being the product of only odd numbers, are odd. This makes
the sum of seven odd numbers, and, subsequently, odd.
The correct choice is that all three scenarios are possible.
If exactly two of are odd, then exactly one of the seven expressions being added is odd - namely, the only one that does not have an even factor (for example, if
and
are odd, then the only odd number is
). This makes
the sum of one odd number and six even number and, subsequently, odd.
If exactly three of are odd, then exactly three of the seven expressions being added are odd - namely, the three that do not include the even factor (for example, if
,
, and
are odd, then the three odd numbers are
,
, and
). This makes
the sum of three odd numbers and four even numbers and, subsequently, odd.
If all four of are odd, then all of the seven expressions being added, being the product of only odd numbers, are odd. This makes
the sum of seven odd numbers, and, subsequently, odd.
The correct choice is that all three scenarios are possible.
← Didn't Know|Knew It →