Grace's age is 3/8th the age of her grandmother. Her grandmother is twice the age of Grace's mother. If Grace's mother is 80 years old, how old is Grace?
How old is Grace's grandmother? ** Grace's grandmother is 2 * 80 years = <<2*80=160>>160 years old.
How old is Grace? ** Grace's age is 3/8 * 160 years = <<3/8*160=60>>60 years old.
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