Question
The present average age of X, Y, and Z is 45 years. 8
years ago, the average age of X and Y was 38 years. What is the present age of Z?Solution
Let X, Y, and Z be P, Q, and R years old respectively. (presently) According to the question, (P + Q + R) ÷ 3 = 45  (P + Q + R) = 135     .... (1) {(P - 8) + (Q - 8)} ÷ 2 = 38  P + Q - 16 = 76  P + Q = 76 + 16  P + Q = 92     .... (2) Putting the value from (2) to (1), The present age of Z is 43 years.
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