`@Mon`
`\text{ Bài 1: Tính nhanh}`
`a)6,28xx18,24+18,25xx3,72`
`=18,24xx(6,28+3,72)`
`=18,24xx10`
`=182,4`
`b)35,7xx99+35+0,7`
`=35,7xx99+(35,07)`
`=35,7xx(99+1)`
`=35,7xx100`
`=3570`
`c)17,34xx99+18-0,66`
`=17,34xx99+17,34`
`=17,34xx(99+1)`
`=1734`
`d)0,9xx95+1,8xx2+0,9`
`=0,9xx(95+4+1)`
`=0,9xx100`
`=90`
`e)0,25xx611,7xx40`
`=(0,25xx40)x611,7`
`=10xx611,7`
`=6117`
`g)37,2x101-37-0,2`
`=37,2xx101-(37+0,2)`
`=37,2xx101-37,2`
`=37,2xx(101-1)`
`=37,2xx100`
`=3720`
`\text{ Bài 2:Tính nhanh}`
`a)(100+67)xx67+(200-33)xx33`
`=167xx167+167xx33`
`=167xx(67+33)`
`=167xx100`
`=16700`
`b)45,651xx73+45,651xx20+45,651xx7`
`=45,651xx(73+20+7)`
`=45,651xx100`
`=4565,1`
`c)14,2xx30+14,2xx57+14,2xx13`
`=14,2xx(30+57+13)`
`=14,2xx100`
`=1420`
`d)72+36xx2+24xx3+18xx4+12xx6+168`
`=72+72+72+72+72+168`
`=72xx5+168`
`=360+168`
`=528`
`e)(8,27+7,16+9,333)-(7,27+6,16+8,33)`
`=8,27+7,16+9,333-7,27-6,16-8,33`
`=1+1+1,003`
`=3,003`
`g)1,5+2,5+3,5+4,5+...+8,5`
`=(1,5+8,5)+(2,5+7,5)+(3,5+6,5)+(4,5+5,5)`
`=10+10+10+10`
`=40`
`h)7,63xx12,47+12,47xx2,37`
`=12,47xx(7,63+2,37)`
`=12,47xx10`
`=124,7`
`i)37,2xx101-37-0,2`
`=37,2xx101-3,72`
`=37,2xx(101-1)`
`=37,2xx100`
`=3720`
`k)112,37xx4,29-4,29xx12,37`
`=4,29xx(112,37-12,37)`
`=4,29xx100`
`=429`
`l)17,4xx52+57xx17,4-17,4xx9`
`=17,4xx(52+57-9)`
`=17,4xx100`
`=1740`
