Multiple choice

In a class of 75 students the average age is 23 years. The average age of male students is 25 years and that of female students is 20 years. Then the ratio of male to female students is-

  1. 8 : 1

  2. 3 : 2

  3. 1 : 2

  4. 2 : 3

  5. None of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Let m = male students, f = female students. Total: m + f = 75. Average age: (25m + 20f)/75 = 23, so 25m + 20f = 1725. From m + f = 75, f = 75 - m. Substituting: 25m + 20(75 - m) = 1725, giving 25m + 1500 - 20m = 1725, so 5m = 225 and m = 45. Then f = 30. Ratio m:f = 45:30 = 3:2. Options A, C, D don't satisfy the average condition.

Keep practicing — related questions