The average of 35 results is 28. The average of first 17 of them is 24 and that of last 17 is 21. Find the 18th result? A) 125 B) 215 C) 512 D) 521

1 Answer

Answer :

B)

Clearly 18th result = (sum of 35 results)- (sum of 34 results)

=(35 * 28) – { (17 *24) +(17 *21)}

= 980 – (408 + 357

=980 – 765

=215

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