Fractionssssssss Over Here!!?

Question

1.) To make one batch of cookies, you need 3/4 cup of butter. How much butter would you need to make 2 1/2 batches of cookies?

2.) A box of laundry detergent contains 35 cups. If you use 1 1/4 cups per load of laundry, how many loads can you wash with 1 box?

Answer 1

1)
3/4 for every batch
2 1/2 is the same as 4/2 + 1/2 = 5/2
Therefore, (by multiplying numerator by numerator and denominator by denominator)
(3/4)*(5/2)=15/8= 1 7/8 cups of butter.

2)
We have 35 cups in a box, and 1 1/4 per load so we will divide them.
First, 1 1/4 is the same as 4/4 + 1/4 = 5/4
Second, 35 cups = 35/1
With division, we can flip a fraction and multiply instead.
Thus, (35/1) / (5/4) is the same as (35/1)*(4/5)
(35/1)*(4/5) = 140/5 =28 loads

Answer 2

3/4 cup of butter for 1 batch of cookies

? cups to make 2.5 batches of cookies

3/4 x5/2(2.5=2 1/2or 5/2)=15/8=1 7/8=1.75 cups of butter

Box of laundry detergent =35 cups , using 5/4 cups per load

35 divided by 5/4= 35/1 x 4/5= 28 loads for 1 box of detergent 5 will become a 1 and 35 will become a 7 4 x7=28

Answer 3

multiply your fractions for number 1. 3/4 * 2 1/2. and that will be your answer. its hard to explain multiplication, but hopefully, if you think about it long enough you'll get it.

for number two, divide the 35 by 1 1/4.

to multiply fractions:
ex.) 1/2 * 5/8
multiply numerators and then multiply denominators, that's your new fraction: 1*5/2*8 = 5/16

if you have a mixed number like 1 4/9 then you need to make it an improper fraction (where you have a bigger number on top of a smaller number) multiply the whole number (in this case 1) by the denominator and then add that answer (9) to the numerator. answer is 13/9 then use this fraction to multiply by the other fraction and you'll get your answer. 13/9 * 5/8 = 65/72 and then reduce.

DIVIDING FRACTIONS:
this is a whole lot easier:

ex.) 4/5 / 7/10
you're going to change the second fraction to a reciprocal, or opposite. so what's the opposite of 7/10? Answer: 10/7

After you change that, multiply the two fractions and that's your answer: 4/5 * 10/7 = 40/35 = 1 5/35 = 1/1/7 (reduced)

if you have another mixed number, follow the steps i gave you to get it to an improper fraction and then divide...

apply this to your problems and you should be fine.

-tiffany

***that sucks that the person who answered it before me gave you the answers...i wanted you to know how to do it next time, not just the freakin answer***

Answer 4

1.
1 one batch= 3/4 cup
3/4*2 1/2
3/4*5/2
15/8=1 7/8 cups

2.
1 box of laundry detergent=35 cups
35/1 1/4
35/5/4
35*4/5
7*4=28 loads

Answer 5

1) 2.5 x 3/4 = 15/8 or 1 7/8 or 1.875

2) 35 / 1 1/4 = 28 loads.

Answer 6

1.) 1:¾ ; 2½:?
multiply ¾ by 2½ ------3/4 X 5/2 -- 15/8 = 1 7/8

2.) 35 devided by 1 1/4
35 devided by 5/4 = 140/5 = 28

Answer 7

1: 1 and 7/8 cups
2: 28