Question 1044921
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36 boys in a class weigh 42 kg on an average. If their teacher is included
The average increases by 1.5kg. How much does the teacher weigh?
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You are given

{{{S/36}}} = 42.                       (1)   (where S is the sum of weights of the 36 boys.
                                       "36 boys in a class weigh 42 kg on an average.")

You are also given 

{{{(S + T)/37}}} = 42 + 1.5 = 43.5.       (2)   (where T is the teacher weight.)


From (1), S = 36*42 = 1512.           (3)

From (2), S + T = 37*43.5 = 1609.5.   (4)

Distract (3) from (4) to get the answer: T = 97.5 kg is the teacher weight.
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