简算3/4x[(7/15-1/5)/2/3].(58+27)x8+19/27.9.56-4.875-1/8+1.44

问题描述:

简算3/4x[(7/15-1/5)/2/3].(58+27)x8+19/27.9.56-4.875-1/8+1.44

3/4x[(7/15-1/5)/2/3]=(3/4)(3/2)(7-3)/15=(9/8)(4/15)=3/10
(58+27)x8+19/27=85x8+19/27=680+19/27
9.56-4.875-1/8+1.44=9.56+1.44-(4.875+0.125)=11-5=6第一个看不懂7/15-1/5通分得:7/15-3/15=4/15