Question
The average age of a man and his two children is 15
years and the average age of man's wife and the same children is 13 years. If the age of man is 31 years, the age of his wife is (in years):Solution
Let the age of two children and wife be x, y and z. ATQ: 31 + x + y = 45 x + y = 14---------(1) Now, x + y + z = 39---------(2) Now, we know that x + y = 14 => x + y + z = 39 => 14 + z = 39 => z = 25 Therefore, age of wife = 25 years
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