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The average age of 30 students of a class is 12 years. The average age of a group of 5 of the students is 10 years and that of another group of 5 of them is 14 years. What is the average age of the remaining students?

A) 8 years
B) 10 years
C) 12 years
D) 14 years

Correct Answer:



C) 12 years

Description for Correct answer:
Total age of 20 students

\( \Large \left(30 \times 12\right) - \left(5 \times 10 + 5 \times 14\right) \)

\( \Large \left(360 - 120\right)years = 240 years. \)

Therefore, Required average = \( \Large \left(\frac{240}{20}\right) = 12 years \)

Part of solved Average questions and answers : >> Aptitude >> Average

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