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The number of stamps that kaye and Alberto had were in the ratio 5:3 respectively. Afer Kaye gave Alberto 10 of her stamps, the ratio of the number of kaye had to the number Alberto had was 7:5. As a result of this gift, kaye had how many more stamps than Alberto?

a) 20
b) 30
c) 40
d) 60
e) 90

Ans given => C

K/A = 5/3
K-10/A+10 = 7/5

Solving these 2 eq, got K = 175 and A = 105. So, Kaye had 70 more stamps than Alberto? Am i missing something here?