Simon and Jimmy had 167 stamps altogether. Simon gave 4/7 of his stamps to Trina, and Jimmy gave 37 stamps to Trina. Simon and Jimmy had the same number of stamps left. How many stamps did Jimmy have in the beginning?

Question

I need you to show me how you did it because I have trouble with these types of questions.

Answer 1

using two variables:

original number of Simons stamps --- x
original number of Jimmy's stamps --- y

x+y = 167 or y = 167-x

after giveaway:
Simon had (3/7)x
Jimmy had (y-37)
--> it says, those two expressions are the same, so
3x/7 = y-37
times 7
3x = 7y - 259
3x - 7y = -259
subbing in the first equation:
3x - 7(167-x) = -259
3x - 1169 + 7x = -259
10x = 910
x = 91
y = 167-91 = 76

Jimmy had 76 stamps at the start.

Answer 2

Argghhh, just noticed that I answered this same question back in 2011

http://www.jiskha.com/display.cgi?id=1294093445