Question 551734
s = her age, b = brother's age
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Now, s = 5b
Next year,
s+1 = 3(b+1) = 3b+3
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s = 3b+2
s = 5b
Sub for s in the 1st equation
5b = 3b + 2
2b = 2
b = 1
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s = 5