human
Emily is 20 years old and her older sister, Rachel, is 24 years old. How old is Rachel when Emily is half her age?
assistant
How old is Rachel when Emily is half her age? ** The difference in age between the two sisters is 24 - 20 = <<24-20=4>>4 years.
How old is Rachel when Emily is half her age? ** When Rachel is twice Emily’s age, she is 4 x 2 = <<2*4=8>>8 years old.
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