Question
In a classroom there are 15 boys and 12 girls. Average
age of each boy and each girl is 21 years and 17 years respectively. The sum of ages of all the boys, girls and a teacher whose age is ‘x’ years is 560 years. Find the value of ‘x’.Solution
Sum of ages of all boys = 15 x 21 = 315 Sum of ages of all girls = 12 x 17 = 204 So, 315 + 204 + x = 560 => x = 41
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