5/7 of the stamps are american and the rest are canadian. There are 108 more American stamps than canadian. How many stamps in all?

Answer 1

a = c + 108

a = 5/7 x (a+c)

a = 5a/7 + 5c/7

7a = 5a +5c

2a = 5c

2(c+108) = 5c

2c +216 = 5c

3c = 216

c = 72 canadian stamps

a = 180 american stamps

total stamps = 252

180 = 5(180)/7 +5(72)/7

180 = 5/7 x 252 = 5(36) = 180