Question

The average of some natural numbers is 15. If 30 is added to first number and 5 is subtracted from the last number the average becomes 17.5 then the number of natural number is ?

Q: The average of some natural numbers is 15. If 30 is added to first number and 5 is subtracted from t

The average of n natural number = 15 New average of n natural numbers = 17.5 ATQ, (17.5) n = (15) n + 30 – 5 17.5 n – 15 n = 25 n = 10

A 10

B 30

C 20

D 15

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Question

The average of some natural numbers is 15. If 30 is added to first number and 5 is subtracted from the last number the average becomes 17.5 then the number of natural number is ?

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