Question

an administrative assistant at a software company often provides breakfast when there is a morning meeting. for last weeks sales, she purchased 3 dozen doughnuts and 5 dozen croissants, spending a total of $60. in preparation for yesterday's safety meeting, she spent $65 on 4 dozen doughnuts and 5 dozen croissants. assuming she purchased the items at the same bakery both times, how much does a dozen of each cost?

Answer 1

donuts: $5.00

croissants: $9.00

Explanation:

c - croissants

d - donuts

(1) 3d + 5c = 60

(2) 4d + 5c = 65

solve for 5c in equation (1)

5c = 60 -3d

substitute 5c = 60-3d into (2)

4d + (60 - 3d) = 65

d + 60 = 65

d = 5

to find c substitute d = 5 into (1)

3(5) + 5(c) = 60

15 + 5c = 60

5c = 45

c = 9