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The average age of a group of 12 students is 20 years, If 4 more students Join the group, the average age increases by 1 year, the average age of the new student is-
The total age of the 12 students is 1220 = 240 years. If 4 more students join the group, the total number of students becomes 12+4 = 16. The total age of the 16 students is (240+4x) years, where x is the average age of the new students. We know that the average age of the 16 students is 21 years. Therefore, the total age of the 16 students is also 2116 = 336 years. Hence, we have the equation 240+4x = 336. Solving for x, we get x = (336-240)/4 = 24. Therefore, the average age of the new students is 24 years.
So the answer is 24
