Sat math question i need to understand

Test Preparation SAT Preparation
1

At first stop after a school bus left the school, 4 children got off the bus. One-quarter of the remaining children got off at the second stop and 10 children got off at the third stop. if there were still 14 children on the bus after third stop.how many children were on the bus as it left the school?
A)28
B)32
C)34
D)35
E)36

THE answer is E

2

Hint: Work backwards. How many children were on the bus right before the 3rd stop? Right before the 2nd stop? 1st stop?

3

Precisely. To summarize, the question says this:

  • 1st stop: 4 kids get off (-4)
  • 2nd stop: 25% get off (meaning that 75% stay)
  • 3rd stop: 10 kids get off (-10)
  • The amount of kids after 3rd stop = 14

Working backwards, 14 + 10 = 24. There are 24 kids on the bus after the 2nd stop.

24/(0.75) = 32. There are 32 kids on the bus after the 1st stop.

32 + 4 = 36. There are 36 kids on the bus as it left school, hence why we choose E. 36

Hopefully this was helpful. (:

4

Thank you all :slight_smile:
MITer94 your hint was really helpful and lynkos your answer was more than enough haha
Thank you

5

For those who are not as gifted at math, you could start with choice C and see if it works. You’ll find its too low (and includes fractions of children which doesn’t make sense) and then try D or E, eventually ending up at E either way.