It is C, "What type of paper are most greeting cards made with."
Answer:
50 cents
Step-by-step explanation:
Let's set up a system of equations. Let x be a cookie and y be a brownie then...
x+2y=2x+y
x+y=1
We can solve this using substitution
x=1-y
1-y+2y=2(1-y)+y
1+y=2-2y+y
1+y=2-y
-1=-2y
y=1/2
One brownie costs 50 cents and one cookie costs...
x+1/2=1
x=1/2
One cookie costs 50 cents
