八乘负五分之二减负四乘负九分之二加负八乘五分之二= 8 x ( -2/5 ) - 4 x 2/9 - 8 x 2/5 = 8 x ( -2/5 ) - 8 x 2/5 - 4 x 2/9 = - 8 x 4/5 - 8/ 9 = - 32/5 - 8/9= - 328 /45- 45 分之 328 施主,我看你骨骼清奇,器宇...