The ratio of the number of magnets Aspilla and Barry had was 2 : 3. When Aspilla bought 4 more magnets and Barry bought 13 more magnets, the ratio became 1 : 2. Find the number of magnets Barry had in the end.
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The ratio of the number of magnets Aspilla and Barry had was 2 : 3. When Aspilla bought 4 more magnets and Barry bought 13 more magnets, the ratio became 1 : 2. Find the number of magnets Barry had in the end.
A / B = 2 / 3 crossmultiply ——>> 3 • A = 2 • B ——>> 3A = 2B (eq 1)
(A+4) / (B+13) = 1 / 2 crossmultiply ——>> 2 • (A+4) = 1 • (B+13) ——>> 2A + 8 = B + 13 (eq 2)
multiply (eq1) by 2 6A = 4B (eq 3)
multiply (eq 2) by 3 6A + 24 = 3B + 39 (eq 4)
per (eq 3) 6A = 4B so substitute 4B into (eq 4)
4B + 24 = 3B + 39
4B – 3B = 39 – 24
B = 15 btw, this means that A = 10
but the problem didn't ask for A
add the 13 that B bought B + 13 = 28
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