The 200 seventh graders at John Witherspoon Middle School ra

[BTGmoderatorDC]

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

OA D

Source: Princeton Review

[deloitte247]

Cost of Trip = T
Unexpected discount at 20 dollar processing fee $$=\ 10\%\ of\ \ \left(T-20\right)$$
Total student = 200
Cost per cookie = 0.1 dollar
Driver's fee = 18 dollar
Surplus = (200*0.3) +18 = 60 +18 = 78 dollars
$$10\%\ of\ \left(T-20\right)=78\ dollar$$
$$\frac{10}{100}\left(T-20\right)=78$$
$$\frac{\left(T-20\right)}{10}=78$$
$$T=780+20$$
$$T=800$$
$$School\ paid\ 20\%\ of\ \cos t\ of\ trip\ \left(T\right)\ \frac{20}{100}\cdot800=160dollars$$
$$answer\ is\ Option\ D$$

[Scott@TargetTestPrep]

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

OA D

Source: Princeton Review

We can let n = the total cost of trip.

n = 0.9(n - 20) + 0.3(200) + 18

n = 0.9n - 18 + 60 + 18

0.1n = 60

n = 600

Since the school paid 20% of the total cost of the trip, the school paid 0.2 x 600 = $120.

Answer: D