Question

Joe sold a total of 10 baked goods. Each cookie costs $1.25 and each brownie costs $2.50. Joe made $20 at the bake sale. How many cookies did Joe sell?

Answer 1

Answer:

4 cookies

Step-by-step explanation:

Let the number of cookies he sold be c and that of brownies be b.

Assuming that brownies and cookies are the only type of baked goods sold,

b +c= 10 -----(1)

Amount of money received= $20

b(cost of brownie) +c(cost of cookie)= $20

2.50b +1.25c= 20 -----(2)

From (1): b= 10 -c -----(3)

Substitute (3) into (2):

2.50(10 -c) +1.25c= 20

Expand:

2.50(10) +2.50(-c) +1.25c= 20

25 -2.50c +1.25c= 20

-1.25c +25= 20

Being constants to 1 side:

-1.25c= 20 -25

-1.25c= -5

c= -5 ÷(-1.25)

c= 4

Thus, Joe sold 4 cookies.