Question
In a College with 1200 students, the average age of the
boys is 24 years and that of girls is 17 years. If the average age of the college is 22 years and 3 months. Find the number of girls in the college?Solution
Alternate Method: By Alligation Boys Girls 24 17 89/4 Multiplying by 4 Boys Girls 96 68 89 Ratio 21 : 7 or 3 : 1 So number of boys = 3/4 of 1200 =900 and number of girls = 1/4 of 1200 = 300
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