A family has five children. The average age of the children is 10 years. If the oldest child is 15, what is the average age of the other four?
Category: Math · Difficulty: expert
Hint: Calculate the total ages first.
Answer
9.75
Explanation
Total age = 5 * 10 = 50. Subtract 15 (the oldest), leaving 35 for the other four, averaging 35/4 = 9.75.
This is a expert math riddle — one of the harder riddles here. The answer is 9.75.
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