... nghÌo; ba chi ® i 7A, 7B, 7C ®· quyªn gãp ®ỵc 120 ngh×n ®ång. TÝnh sè tiỊn m i chi § i quyªn gãp ®ỵc? BiÕt r»ng sè tiỊn quyªn gãp cđa c¶ ba chi § i lÇn lỵt tØ lƯ v i 4; 5; 6. B i 5. (1,0 i m)Cho ... có: µµµ0A B C 180+ + =(0, 25 i m)µ0 0 0 56 B 72 180+ + =(0, 25 i m) µ0 0 0B 180 ( 56 72 )= − +(0, 25 i m) µ0B 52 =(0, 25 i m) B i 2. (1 ,5 i m)a) 7 4 17 24 10 7 17 1 4 10 ... =(0 ,5 i m)b) 108.7 + 108.23 - 30.8 = 108(7 + 23) - 30.8 = 108.30 - 30.8 = 30(108 - 8) = 30.100 = 3000 (0 ,5 i m)c) 221 1 1 1 1 1 5 5 0 5 5 5 5 5 5 × − − = × − = − = ÷ (0 ,5 i m)Bài...