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If out of 10 selected students for an ex...

If out of 10 selected students for an examination, 3 were of 20 years, age, 4 of 21 and 3 of 22 years, the average age of the group is:

A

20 years / 20 वर्ष

B

22 years / 22 वर्ष

C

21 years / 21 वर्ष

D

21.5 years / 21.5 वर्ष

Text Solution

Verified by Experts

The correct Answer is:
C
पुरे वर्ग की औसत आयु `=(3xx20+4xx21+3xx22)/(10)`
`=(210)/(10)`
`=21` वर्ष
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