更新时间2019-04-03 14:52:14
解;2/3+7/5
=(2×5)/(3×5)+(7×3)/(5×3)
=10/15+21/15
=31/15
=2又1/15
2/3+7/5=(2*5+3*7)/(3*5)=31/15
原式=2/3+1+2/5=1+1+1/15=2又1/15。
这个是十五分之三十一的了
十五分之三十一
2/3+7/5
=2*5/(3*5)+7*3/(5*3)
=10/15+21/15
=31/15
2/3+7/5
= (2x5)/(3x5) + (7x3)/(5x3)
= 10/15 + 21/15
= (10+21)/15
=31/15