Sarah needs to make a cake and some cookies. The cake requires 3/8 cup of sugar and the cookies require 3/5 cup of sugar. Sarah has 15/16 cups of sugar. Does she have enough sugar, or how much more does she need?
2007-12-19 03:28:12 · 8 answers · asked by Init05 2 in Science & Mathematics ➔ Mathematics
no, 80 is the common denominator, and 3/8 is 30/80
3/5 is 48/80, so she needs 78/80.
She only has 15/16 which is 75/80.
She needs 3/80 cup more.
2007-12-19 03:36:48 · answer #1 · answered by ? 5 · 1⤊ 0⤋
Sarah needs to make a cake and some cookies. The cake requires 3/8 cup of sugar and the cookies require 3/5 cup of sugar. Sarah has 15/16 cup of sugar. Does she have enough sugar, or how much more does she need? Sugar required is (3/8 + 3/5) cup or 39/40 cup Sugar available is 15/16 cup Sugar needed is (39/40 - 15/16) cup = (78/80 - 75/80) cup C. She needs 3/80 of a cup of sugar.
2016-04-10 07:40:54 · answer #2 · answered by ? 4 · 0⤊ 0⤋
1st put everything in to a common denominator. Your denominators are 8, 5, and 16 --- so you need to find the least common multiple of those = 80.
Now rewrite the fractions with denominator of 80:
(3/8) = (30/80)
(3/5) = (48/80)
(15/16) = (75/80)
Add the first two:
(30/80) + (48/80) = (78/80)
Since she has (75/80), there is not enough sugar.
2007-12-19 03:36:52 · answer #3 · answered by miggitymaggz 5 · 0⤊ 0⤋
okay this is what you do you find common denominators so
3/8(5/5)+3/5(8/8)= 15+24/40= 34/40 okay and then you have to find common dnomintors between 15/16 and 34/40 so you multiply each by the bottom number so you get 600/640 and then for 34/40 you get 544/640 so you will have enough sugar because 544 is less than 600 .
2007-12-19 03:38:44 · answer #4 · answered by angel_babydoll_devil08 2 · 0⤊ 1⤋
to compare fractions, you need to convert all of them so that they have the same bottom number (denominator), or convert them all to decimals. Decimals can be easier:
3/8 = .375
3/5 = .6
15/16 = .9375
so, how does (.375+.6) compare to .9375 ?
Sarah needs .975, but she only has .9375, so she needs .0375 more...
To go the fraction way of converting, you can convert all the fractions to x/80 (80 is 5x16, the least common denominator)
3/8 = 30/80
3/5 = 48/80
15/16 = 75/80
Sarah needs 78/80 cups, but only has 75/80, which means she needs 3/80 cups more..
3/80 is the same as the .0375 !
2007-12-19 03:44:14 · answer #5 · answered by Joe K 3 · 0⤊ 0⤋
3/8+3/5 = 15/40 + 24/40= 39/40 = .975
15/16 =9375
Sorry, she does not have enough sugar.
2007-12-19 03:35:49 · answer #6 · answered by ironduke8159 7 · 0⤊ 0⤋
she has approximate sugar to make cake and cookies
2007-12-19 03:36:03 · answer #7 · answered by hafia k 2 · 0⤊ 0⤋
let the no of of cakes be x & cookies be y
3/8x+3/5y<=15/16
this is the equation, doe she have enough or not depends on how many cakes & cookies she is going to make.
2007-12-19 03:33:52 · answer #8 · answered by Siva 5 · 0⤊ 2⤋