Grace's grandmother is 2 * 80 years = <<2*80=160>>160 years old.

Grace's age is 3/8 * 160 years = <<3/8*160=60>>60 years old.

# Answer

60
<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
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?
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
<|im_start|>assistant

user
60
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?
train