简算13/21×17+17/21×8
问题描述:
简算13/21×17+17/21×8
答
17*13/21+8*17/21
=17*13/21+17*8/21
=[17*(13+8)]/21
=17*21/21
=17*1
=17
答
17*13/21+8*17/21
=17*13/21+17*8/21
=17*(13/21+8/21)
=17*21/21
=17*1
=17
答
13/21×17+17/21×8
=17/21(13+8)
=17/21*21
=17