Question

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?

Answer 1

Step-by-step explanation:

cake -3/8

cookies-5/8

sum of required sugar =3/8+3/5=39/40

Sarah has =15/16 cup of sugar

for req sugar - 39/40-15/16=3/80

Answer 2

Answer:

She not has enough sugar and she need $\frac{3}{80}$ cups more sugar.

Step-by-step explanation:

Given,Sarah needs to make cake and cookies.

For cake require 3/8 cup of sugar and for cookies require 3/5 cup of sugar.

So,total sugar require for both cake and cookies

$= \frac{3}{8} + \frac{3}{5} \\ = \frac{3 \times 5 + 3 \times 8}{40} \\ = \frac{15 + 24}{40} \\ = \frac{39}{40}$

Now it is also given she has $\frac{15}{16}$

cups of sugar.

Now,

$\frac{39}{40} = 0.975$

and $\frac{15}{16} = 0.9375$

It is clear that $\frac{39}{40} > \frac{15}{16}$

So,Sarah need more sugar and she need

$( \frac{39}{40} - \frac{15}{16} ) \\ = \frac{78 - 75}{80} \\ = \frac{3}{80}$ cups sugar more.

This is a problem of Algebra.

Some important Algebra formulas.

(a + b)² = a² + 2ab + b²

(a − b)² = a² − 2ab − b²

(a + b)³ = a³ + 3a²b + 3ab² + b³

(a - b)³ = a³ - 3a²b + 3ab² - b³

a³ + b³ = (a + b)³ − 3ab(a + b)

a³ - b³ = (a -b)³ + 3ab(a - b)

a² − b² = (a + b)(a − b)

a² + b² = (a + b)² − 2ab

a² + b² = (a − b)² + 2ab

a³ − b³ = (a − b)(a² + ab + b²)

a³ + b³ = (a + b)(a² − ab + b²)

Know more about Algebra,

1) https://brainly.in/question/13024124

2) https://brainly.in/question/1169549

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