a) 75.20,9+52.20,9
= 20,9.(75+52)
= 20,9.100
= 2090
b)
b)85.15+150.1,4
= 85.1,4+150+15
= 119+165
= 284
a,75.20,9 + 52.20,9=20,9(75+52)=20,9.100=2090
b,85.15 + 150.1,4=15(85+14)=15.99=1485
d,98,6.199-990.9,86=98,6(199-99)=9860
c,93.32+14.16=93.32+7.2.16=32(93+7)=3200
a) Ta có: \(75\cdot20.9+5^2\cdot20.9\)
\(=20.9\left(75+25\right)\)
\(=20.9\cdot100=2090\)
b) Ta có: \(85\cdot15+150\cdot1.4\)
\(=85\cdot15+14\cdot15\)
\(=15\cdot99=1500-15=1485\)
c) Ta có: \(93\cdot32+14\cdot16\)
\(=93\cdot2\cdot16+14\cdot16\)
\(=16\left(93\cdot2+14\right)\)
\(=16\cdot200=3200\)
d) Ta có: \(98,6\cdot199-990\cdot9,86\)
\(=98.6\cdot199-98.6\cdot99\)
\(=98.6\cdot100=9860\)
