- A gives B and C as many tractors as they already have.
- After some days B gives A and C as many tractors as they have.
- After some days C gives A and B as many tractors as they have.
- Finally each has 24 tractors.
What is the original number of tractors each had in the beginning?
Submitted by Guess the Logo.
A had 39 tractors, B had 21, C had 12.
ReplyDeleteThis is easiest to figure out if you start the math from the end result and work backwards.
I also worked backwards but got a slightly different answer:
ReplyDeleteA: 40, B: 22, C: 12
Carol, you have too many tractors. In your response, you have 40+22+12=74. There need to be 72 tractors total (24x3=72.)
ReplyDeleteAfter round 3
ReplyDeletea b c
24 24 24
A and B both doubled in round 3, so slice them in half to get A and B and subtract from total 72 to get C. That means that the previous nubers must be...
after round 2
a b c
12 12 48
A and C both doubled in round 2, so the previous numbers were...
after round 1
a b c
6 42 24
Rinse and repeat with B and C
originally
a b c
39 21 12
As Jolson laid out so carefully:
ReplyDeleteA 39
B 21
C 12