42.(15−3)−3.(25−42)42.(15−3)−3.(25−42)
=42.15−42.3−3.25+3.42=42.15−42.3−3.25+3.42
=42.15−3.25=42.15−3.25
=42.3.5−3.5.5=42.3.5−3.5.5
=3.5(42−5)=3.5(42−5)
=15.37=15.37
=555=555
9.(32−5)+459.(32−5)+45
=9.32−9.5+9.5=9.32−9.5+9.5
=9.32=9.32
=288=288
21.83−7.3.1721.83−7.3.17
=21.83−21.17=21.83−21.17
=21(83−17)=21(83−17)
=21.66=21.66
=1386=1386
4.5.(−19)+2.10.1194.5.(−19)+2.10.119
=2.2.5(−19)+2.2.5.119=2.2.5(−19)+2.2.5.119
=2.2.5(−19+119)=2.2.5(−19+119)
=20.100=20.100
=2000=2000
29.(23+15)−23.29+1529.(23+15)−23.29+15
=29.23+29.15−23.29+15=29.23+29.15−23.29+15
=29.15+15=29.15+15
=15(29+1)=15(29+1)
=15.30=15.30
=450=450
(−95)(2−456)−456.95(−95)(2−456)−456.95
=−95.2+95.456−456.95=−95.2+95.456−456.95
=−95.2=−95.2
=−190
