Question
The ratio of the present ages of father and his son is
8:3. The product of their ages 3 years ago was 29 times of his son’s age that year. What was son’s age 2 year ago?Solution
Let present age of father and son be 8x and 3x respectively. According to question,  => (8x – 3) (3x – 3) = 29 × (3x – 3)  => (8x – 3) = 29 => 8x = 32 => x = 4 Therefore, son’s age 2 years ago = (3x – 2) = 10 years
Find the mean of the following observations:
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