第1个回答 2013-05-21
74x10.1=(74 ) ×(10 ) +(74 ) ×(0.1 )
一. 11又7/8-6又1/3-1又2/3
=11又7/8 - (6又1/3+1又2/3 )
=11又7/8 - 8
=3又7/8
.
二.79x101=79×100 + 79×1=7900+79=7979
.
三. 2又1/2x6.4+2.5x6又3/5
=2.5×(6.4+6.6)
=2.5×11
=2.5×10 + 2.5×1
=25+2.5
=27.5
.
四.23-6又7/11-2又5/11-13/11
=23 - (6又7/11 + 2又5/11 + 1又2/11)
=23 - (9又14/11)
=23- 10又3/11
=12又8/11
.
五.(1/8+3/4+5/12)×24
=(1/8)×24 +(3/4)×24+(5/12)×24
=3+18+10
=31
.
六.1.625x1992+1992x3/8-1992
=(1.625+1.625-1)×1992
=(3.25-1)×1992
=2.25×(2000-8)
=2.25×2000 - 2.25×8
=4500 - 18
=4482