Question

脱式计算，（能简便的要简便）3.82÷0.2-0.2×2.5，2.4×1.58+6.6×1.58+1.58，0.48×6.5+5.2×0.65

12.4-12.4×0.25，七分之五-（七分之五-二分之一），0.125×9+1÷8

Answer 1

3.82÷0.2-0.2×2.5

=38.2÷2-0.5

=19.1-0.5

=18.6

2.4×1.58+6.6×1.58+1.58

=1.58x(2.4+6.6+1)

=1.58x10

=15.8

0.48×6.5+5.2×0.65

=4.8×0.65+5.2×0.65

=(4.8+5.2)×0.65

=10×0.65

=6.5

12.4-12.4×0.25

=12.4×(1-0.25)

=12.4×3/4

=3.1×3

=9.3

七分之五-（七分之五-二分之一）

=5/7-5/7+1/2

=1/2

0.125×9+1÷8

=9x1/8+1x1/8

=(9+1)x1/8

=5/4