1、5.76+ 13.67+4.24+6.33
=(5.76+4.24)+( 13.67+6.33)
= 10+20
=30
Example 2, 37.24+23.79- 17.24
=37.24- 17.24+23.79
=20+23.79
=43.79
Example 3,4× 3.78× 0.25
=4×0.25×3.78
= 1×3.78
=3.78
Example 4: 125×246×0.8
= 125×0.8×246
= 100×246
=24600
Example 5, (2.5+ 12.5) × 40
=2.5×40+ 12.5×40
= 100+500
=600
Example 6, 3.68× 4.79+6.32× 4.79
=(3.68+6.32)×4.79
= 10×4.79
=47.9
Example 7.26.86× 25.66-16.86× 25.66
=(26.86- 16.86) ×25.66
= 10×25.66
=256.6
Example 8, 5.7× 99+5.7
= 5.7×(99+ 1)
=5.7× 100
=570
Example 9, 34×9.9
=34×( 10-0. 1)
=34× 10-34×0. 1
=340-3.4
=336.6
For example, 10,57×101.
=57×( 100+ 1)
=57× 100+57× 1
=5757