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)
[tex]A\text{ + }\frac{3}{5}A\text{ = 4}\frac{1}{6}[/tex]Reordering:
[tex]A+\frac{3}{5}A=\text{ }\frac{25}{6}[/tex]Multiplying both sides by 30:
[tex]30A\text{ + 18A = 25}\cdot5[/tex][tex]48A\text{ = 125}[/tex]Dividing both sides by 48:
[tex]A\text{ = }\frac{125}{48}[/tex]Representing as mix fraction and rounding:
[tex]A=\text{ 2}\frac{2}{3}[/tex]ANSWER: She will need two and two-thirds cups of Recipe A.