8分之7减去(4分之3—4分之3乘以6分之5);
7/8-(3/4-3/4*5/6)
=7/8-(3/4-5/8)
=7/8-1/8
=3/4
(9分之8减去3分之1)除以(2分之1乘以3分之2);
(8/9-1/3)/(1/2*2/3)
=5/9 / 1/3
=5/9*3
=5/3
5分之4乘以2分之1与3分之1的和的积加上3分之1的和是?
4/5*(1/2+1/3)+1/3
=4/5*5/6+1/3
=2/3+1/3
=1
4/5*(1/2+1/3)+1/3
3/4 5/3 42/5即5有2/5
额看着好脑疼啊...