Since the TOTAL area is 30 square inches, what you would do is divide 30/3, since you already know how wide it is. And the answer is 10. The envelope is 10 inches tall.
You can use proportion to solve this
She needs 2 graham crackers ( and other ingredients) to make 1 cookie
Crackers Cookie
2 1
20 X
Cross multiply
x=20*1/2
X= 10
Answer:
0.75
Step-by-step explanation: