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帮我做几道数学题(要简便运算)

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帮我做几道数学题(要简便运算)
33.3乘334+99.9乘222 45.6乘6.7+4.56乘31+0.456乘20
15.8乘5.8+4.2乘4.2+11.6乘4.2
(0.05+0.05+0.05)乘9+0.05乘73
帮我做几道数学题(要简便运算)
*是乘的意思.
1.33.3*334+99.9*222
=33.3*334+33.3*3*222
=33.3*334+33.3*666
=33.3*(334+666)
=33.3*1000
=33300
2.45.6*6.7+4.56*31+0.456*20
=45.6*6.7+45.6*3.1+45.6*0.2
=45.6*(6.7+3.1+0.2)
=456
3.15.8*5.8+4.2*4.2+11.6*4.2
=15.8*5.8+4.2*(4.2+11.6)
=15.8*5.8+4.2*15.8
=15.8*(5.8+4.2)
=15.8*10
=158
4.(0.05+0.05+0.05)*9+0.05*73
=0.05*3*9+0.05*73
=0.05*27+0.05*73
=0.05*(27+73)
=0.05*100
=5