Question
A’s age is the seventh part of his father’s
age. After 10 years, the age of A’s father will be twice the age of B. If B’s 5th birthday is celebrated 4 years ago, then what is the current age of A?Solution
Let A’s age be x years and father’s age be 7x years. Present age of B = 5 + 4 = 9 years After 10 years, => 7x + 10 = 2(9 + 10) => 7x = 38 – 10 => x = 28/7 = 4 years
Find the mean of the following observations:
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