The average weight of a group of 20 boys was calculated to be 65 kg and it was later discovered that the weight of a boy was misread as 76 kg instead of the correct weight 66 kg. The correct average weight was:

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The average weight of a group of 20 boys was calculated to be 65 kg and it was later discovered that the weight of a boy was misread as 76 kg instead of the correct weight 66 kg. The correct average weight was:

A66 kg

B63 kg

C65.5 kg

D64.5 kg

Answer:

D. 64.5 kg

Read Explanation:

Correct average weight = (20 × 65 - 76 + 66)/20 ⇒ 1290/20 ⇒ 64.5 kg