Question
The average age of (x + 3) people in a group is 20 years.
When a new member aged 43 joins, the average becomes 21. Find x% of 500.Solution
Total age of group = 20(x + 3)
According to question,
[20(x + 3) + 43] = 21(x + 3 + 1)
20x + 60 + 43 = 21x + 84
21x - 20x = 103 - 84
x = 19
So, 19% of 500 = 95
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