Bunuel wrote:
The 200 seventh graders at John Witherspoon Middle School raised 80% of the funds needed for a field trip. The school donated the remaining 20%. When they went to purchase the tickets, however, they were given a 10% bulk rate discount after a $20 processing fee. Faced with an unexpected surplus the students chose to buy each member of the class one cookie and were still left with $18, which they gave to the bus driver. If each of the cookies cost $0.30, how much did the trip cost the school?
A. $40
B. $80
C. $120
D. $160
E. $200
We can let n = the total cost of trip. They were charged: a processing fee of $20, 90% of the remaining n - 20, 200 cookies at $0.3 each. They also paid $18 to the driver; therefore:
n= 20 + 0.9(n - 20) + 0.3(200) + 18
n = 20 + 0.9n - 18 + 60 + 18
0.1n= 80
n = 800
Since the school paid 20% of the total cost of the trip, the school paid 0.2 x 800 = $160.
Answer:D
_________________
5-star rated online GMAT quant
self study course
See why Target Test Prep is the top rated GMAT quant course on GMAT Club. Read Our Reviews
If you find one of my posts helpful, please take a moment to click on the "Kudos" button.