Solved UPSC CDS/OTA Question
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The average weight of 4 men A, B, C and D is 67 kg. The 5th man E is included and the average weight decreases by 2 kg. A is replaced by F. The weight of F is 4 kg more than E. Average weight decreases because of the replacement of A and now the average weight is 64 kg. Find the weight of A
Step-by-Step Solution
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Sum of the weights of A, B, C and D
= 67 × 4 = 268 kg and average weight of A, B, C, D and E = 67 – 2 = 65 kg
∴ Sum of the weights of A, B, C, D and E =
65 × 5 = 325 kg
∴ Weight of E = 325 – 268 = 57 kg
∴ Weight of F = 57 + 4 = 61 kg
Now, average weight of F, B, C, D and E = 64 kg
∴ Sum of the weights of F, B, C, D and E = 64 × 5 = 320 kg
∴ Sum of the weights of B, C and D
= 320 – 57 – 61 = 202 kg
∴ Weight of A = 268 – 202 = 66 kg