A. 17 kg
B. 20 kg
C. 26 kg
D. 31 kg
Let A, B, C represent their respective weights. Then, we have: A + B + C = (45 x 3) = 135 …. (i) A + B = (40 x 2) = 80 …. (ii) B + C = (43 x 2) = 86 ….(iii) Adding (ii) and (iii), we get: A + 2B + C = 166 …. (iv) Subtracting (i) from (iv), we get : B = 31. B’s weight = 31 kg
Related Mcqs:
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1 Comment
The average weight of A, B and C is 45 kg. If the average weight of A and B be 40 kg and that of B and C be 43 kg, then the weight of B is___________?
A. 17 kg
B. 20 kg
C. 26 kg
D. 31 kg
Solⁿ:
Total weight of A,B,C=45*3=135Kg
Total weight of A,B=40*2=80 Kg
Weight of C=135-80=55 Kg
Total weight of B+C=43*2=86 Kg
Therefore weight of B=86-55=31 Kg
Answer: 31 Kh