How to multiply and divide decimals - HSPT Math

First find out how many gallons of gas the car consumed while traveling 1150 miles. This can be found out like so:

1150 miles x gallons/46 miles = 25 gallons

Multiplying 25 by $3.90 yields $97.50.

The given dimensions must be multiplied by 5, so 2.5 inches becomes 12.5 feet, and 3 inches becomes 15 feet.

and

Using the factor-label method we get the following equation.

We treat the units as if they are numbers, and can cancel the units from the fractions.

Convert to scientific notation by creating a number that is greater than or equal to 1 AND less than 10 AND includes the same digits as the original number. Remove all zeros before the first natural number and after the last natural number.

So, we have 48,570.

Now we move the decimal to create our number between 1 and 10.

4.8570

We have one zero after the last natural number, which is 7. Remove that.

4.857

Now we must multiply that number by 10 to a certain power. We choose our power by how many places the decimal must move to get our original number. In this case, the decimal would have to move 4 places to the right.

4.857

48.57

485.7

48,570.

So our final answer is

Set the equation up as

Solve for , which equals

or

Therefore the percent sales tax is:

To multiply, there is no need to solve for a least common denominator. Simply multiply the numerator with the numerator and the denominators together.

Multiply the terms as is, ignoring the decimal.

Since there is one decimal from the original problem, the decimal place is one unit from the right. Therefore, the final answer must have a decimal one unit to from the right.

The answer is .

The group wants a total of strips; since

,

Dave will need to purchase five orders of strips (he cannot purchase a partial order). This will cost him

.

The formula to calculate distance is where represents rate of speed and represents time.

In this problem, mph., and hours.

Convert the to an improper fraction:

To solve, multiply.

miles.

At its cruising speed of mph, the aircraft will travel miles in hours.

First,

Then,

When multiplying decimals you ignore the decimals and multiply the two numbers like you would normally.

Then count the total number of decimal places to the right of the decimal of the original numbers.

Move the decimal from the whole number answer you just received to the left the same number of times as the total decimal places to the right of the numbers before you multiplied them.

Therefore the answer is

To solve:

First, find what is 20% of 55 by multiplying:

Then, subtract 20% (11) from the original price:

The final sale price will be $44.00.

To solve:

First find the corresponding percentage of each multiple choice answer,

a)

b)

c)

d)

Then, compare the amounts and select which amount is the largest:

b) 60

Examine the divisor 0.004. To make this a whole number, the decimal point needs to be moved three places right. Do this to both 0.004 and 320, adding an implied decimal point after the latter first:

Now perform this division:

First, multiply, ignoring the decimal points:

Put a decimal point after the number:

Since there were five digits total (one per factor) left of the decimal points, move the decimal point in the product left five places, inserting zeroes as needed:

The fraction has its last nonzero digit in the hundredths place, so write the number, without the decimal point, over 100. Then reduce.

To rewrite a very large number in scientific notation:

Write the number with the decimal point after it (it is implied to be at that location).

Move the decimal point left as many places as needed until it follows the first nonzero digit, which here is the four. Count the number of places it is moved - here it will be eleven places.

The number formed is , which will be placed in front; 11, the number of places counted, will be the exponent. The number, in scientific notation, will be .

is equal to , which is 20%.

Divide 8 by 15:

The 3 repeats, so the correct choice is .