Three boys shared some oranges. The first received 31 of the oranges and the second received 32 of the remainder. If the third boy received the remaining 12 oranges, how many oranges did they share?
Worked solution (try it first)
After the first boy takes 31, the remainder is 1−31=32 of the oranges.
The second takes 32 of that remainder, so the third gets the other 31 of it: 31×32=92 of all the oranges.
So 92 of the total is 12.
One ninth is 12÷2=6, and the total is 6×9=54, option B.