Multiple choice

There were 24 students in a class. One of them who was 18 year old left the class and a new student joined and the average age of class reduced by 1 month. Find the age of newcomer.

  1. 14 years

  2. 15years

  3. 16 years

  4. 17 years
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Total age change = (number of students) * (change in average). The average reduced by 1 month (1/12 year). Total change = 24 * (-1/12) = -2 years. The new student is 2 years younger than the one who left. Age = 18 - 2 = 16.

AI explanation

The total age decrease for the class is 24 students multiplied by 1 month, which equals a total reduction of 24 months, or 2 years. Because the original student who left was 18 years old, the new student must be 2 years younger to create this exact decrease in the overall sum. Subtracting 2 years from 18 years means the age of the newcomer is 16 years.

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