Question
A person’s present age is 4/5th of the age of his
brother. After 10 years, he will be 9/10th of the age of his brother. How old is the brother at present?Solution
Let the brother’s present age be x years. Then, The person’s present age = 4/5 x ⇒ 4x/5 + 10 = 9/10(x + 10) ⇒ 9x/10 – 4x/5 = 10 - 9 5x/50 = 1 x = 10 Brother’s age = 10 years.
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