Mike is 16 years old. His sister Barbara is half as old as he is. How old is Barbara going to be when Mike is 24 years old?
How old is Barbara currently? ** Barbara is currently 16 years / 2 = <<16/2=8>>8 years old.
How old will Mike be after 24 years? ** Mike is going to be 24 years old after 24 years - 16 years = <<24-16=8>>8 years.
How old will Barbara be when Mike is 24 years old? ** So Barbara is going to be 8 years + 8 years = <<8+8=16>>16 years old.
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