计算过程如下:7/15-(2/7+2/15)=7/15-2/7-2/15=7/15-2/15-2/7=5/15-2/7=1/3-2/7=7/21-6/21=1/21,答案为二十一分之一。希望可以帮到你,望采纳!
7/15-(2/7+2/15)
=7/15-2/7-2/15
=1/3-2/7
=7/21-6/21
=1/21
7/15-(2/7+2/15)
=7/15-2/7-2/15
=7/15-2/15-2/7
=5/15-2/7
=1/3-2/7(异分母分数加减法通分成同分母加减法)
=7/21-6/21
=1/21
7/15-(2/7+2/15)
=7/15-2/15-2/7
=5/15-2/7
=1/3-2/7
=7/21-6/21
=1/21
望采纳 谢谢~~
7/15-(2/7+2/15)
=7/15-2/15-2/7
=1/3-2/7
=7/21-6/21
=1/21