How to Multiply Fractions by Whole Number

Question

Mrs. Jayde is baking 9 cakes for a bake sale. The cake recipe calls for 3/8 cup of sugar for each cake. How many cups of sugar will she need in all.

Answer 1

All numbers can be written as fractions: 9=9/1. The rule when multiplying fractions is multiply the numerators to get your new numerator and the denominators by to get your new denominator. So 3/8 times 9/1 is 27/8 because 3 * 9 is 27 and 1 * 8 is 8. Then simplify: 8 * 3 is 24 so the answer as a mixed number is 3 + 3/8.

Answer 2

Hello,

Since each cake requires 3/8 cup of sugar, 9 cakes would 3/8 of a cup of sugar 9 times

3/8 x 9 can be rewritten as 3/8 x 9/1 since all whole numbers can be rewritten as a fraction with a 1 as the denominator

The two numerators are 3 and 9 and the two denominators are 8 and 1. To solve the product of fractions, you simply have to multiply the two numerators and the two denominators

3 x 9 = 27 8 x 1 = 8 so, you get the fraction of 27/8

To simplify, 27 divided by 8 = 3 with a remainder of 3

In other words. the whole number 3 can be expressed as the fraction 24/8

27/8 - 24/8 = leaves a remainder of 3/8, so the answer would be 3 3/8 cups of sugar

Answer 3

Hello,

One of the basic things in math is if you know what happens with 1 item then you can figure out what happens with many items

in this case, we know that each cake requires 3/8 of a cup of sugar

So if 1 cake requires 3/8 then nine cakes will require 9 cakes times 3/8 cup of sugar

Now let’s set up the multiplication to get to the total cups of sugar required for nine cakes

Because we’re gonna have a whole number multiplied by a fraction let’s make the whole number look like a fraction also

Any whole number can be represented as a fraction by taking that whole number divided by one

Please note that the number on top of a fraction is called the numerator and the number on the bottom is called a denominator

(9/1) times (3/8)

when multiplying two fractions together, you multiply the two numerators times each other and the two denominators times each other

9 times 3 is 27

1 times 8 is 8

So when multiplying the two fractions together, you get 27/8

We want to know how many cups of sugar is needed so we need to take this fraction and convert it into whole cups and a fraction of a cup

you need to figure out how many whole denominators will divide into the numerator

27÷8 is three with three left over so the fraction is 3 and 3/8

So final answer is 3 3/8 cups of sugar to bake nine cakes

Answer 4

Answer 5