There are two groups of a class consisting of 72 and 88 students respectively. If the average weight of 1st group is 80kg and the weight of 2nd group is 70kg. Find the average weight of whole class? A) 64kg B) 74.5kg C) 84.5kg D) 54kg

1 Answer

Answer :

 B)

 Total weight of (72 + 88) = (72*80) + (88 * 70)kg

= (5760 + 6160)kg

 = 11,920kg

 Average weight of the whole class = 11920 / 160

 = 74.5 kg


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