Question

2.6×0.7×0.8的简便计算

Answer 1

2.6×0.7×0.8
=2.6×7×8÷100
=2.6×0.56
=2.6×(0.5+0.06)
=2.6×0.5+2.6×0.06
=2.6×5÷10+2.6×6÷100
=13÷10+15.6÷100
=1.3+0.156
=1.456

Answer 2

39.3*7.2+26.8*2.8
=(12.5+26.8)x7.2+26.8x2.8
=12.5x7.2+26.8x7.2+26.8x2.8
=12.5x8x0.9+26.8x(7.2+2.8)
=100x0.9+26.8x10
=90+268
=358