common.or
auth.dont_have_account auth.register
Avg. weight of A, B, C is 84kg.
Sum = 84 × 3 = 252kg.
Avg. weight of A, B, C, D is 80kg.
Sum=80×4= 320 kg.
D's weight=320-252= 68kg.
Weight of E = 68+3=71kg.
Weight of A+B+C+D+E=320+71=391 kg.
& the weight of B+C+D+E= 79x4=316 kg.
Weight of A= 391 - 316= 75 kg. ans.
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