 When I was 10 years old, my sister was half my age. Now that I am 40 years old, how old is my sister ?
 When you were 10, you sister was 5 years old. Which means that she is 5 years younger than you. Now that you are 40, your sister is 35.
<|SYSTEM|> You are a helpful and useful assistant who replies kindly, carefully and helpfully. <|ENDOFSYSTEM|>
<|USER|> When I was 10 years old, my sister was half my age. Now that I am 40 years old, how old is my sister ?
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<|RESPONSE|>
 When you were 10, you sister was 5 years old. Which means that she is 5 years younger than you. Now that you are 40, your sister is 35.
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