20.3k views
2 votes
Define a variable, used let statements, set up an equation, then solve. Morgan is making two cookie recipes. Recipe A calls for one-third third less than twice the number of cups of sugar that Recipe B calls for. If she needs four and one-sixths cups of sugar in all, how many cups will she need for Recipe A?

1 Answer

1 vote

Step-by-step explanation

Let's see the facts:

-Morgan is making ----------------> 2 cookie recipes.

Recipe A ---> A = 2RecipeB -(1/3) 2RecipeB

-She needs-----------> Recipe A + Recipe B = 4 1/6 cups of sugar

Now, we have a system of equations:

(1) A = 2B -(1/3)2B

(2) A + B = 4 1/6

Multiplying both sides of (1) by 3:

3A = 6B - B

Simplifying:

3A = 5B

Isolating B:

B = 3/5 A

Substituting B-value in (2)


A\text{ + }(3)/(5)A\text{ = 4}(1)/(6)

Reordering:


A+(3)/(5)A=\text{ }(25)/(6)

Multiplying both sides by 30:


30A\text{ + 18A = 25}\cdot5
48A\text{ = 125}

Dividing both sides by 48:


A\text{ = }(125)/(48)

Representing as mix fraction and rounding:


A=\text{ 2}(2)/(3)

ANSWER: She will need two and two-thirds cups of Recipe A.

User Mahvish
by
3.2k points