Question
 The average age of 12 boys in a group is 8 years. If
3 more boys join the group, the average is increased by 1 year. What is the average age (in years) of the three new boys in the group?Solution
The average age of 12 boys in a group=8 years Total Age =12×8=96 years 3 more boys join the group so the total boys =12+3=15 boys And increased average by 1=8+1=9 years So total age of 15 boys =15×9 =135 years total age of new 3 boys =135-96=39 years average age of new 3 boys = 39/3=13 years Â
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