(1)49.5×10又3/5-(50-1/2)×0.6 (2)91×1/13-1÷13×100+9÷13 (3)2×1/5+5×2/11+4×2/5+3×4/11
问题描述:
(1)49.5×10又3/5-(50-1/2)×0.6 (2)91×1/13-1÷13×100+9÷13 (3)2×1/5+5×2/11+4×2/5+3×4/11
简便计算,用 逆用分配率 来做
答
(1)49.5×10又3/5-(50-1/2)×0.6
=49.5×10.6-49.5×0.6
=49.5×(10.6-0.6)
=49.5×10
=495
(2)91×1/13-1÷13×100+9÷13
=(91-100+9)×1/13
= 0×1/13
=0
(3)2×1/5+5×2/11+4×2/5+3×4/11
=(2+8)×1/5+(10+12)×1/11
=10×1/5+22×1/11
=2+2
=4