thực hiện phép tính:

`1)`

`0,5\sqrt{0,04}+5\sqrt{0,36}`

`=0,5.0,2+5.0,6`

`=0,1+3`

`=3,1`

`2)`

`-4\sqrt{(-25)/(-16)}+5\sqrt{(-9)/(-25)}`

`=-4.1,25+5.0,6`

`=-5+3`

`=-2`

`3)`

`2/3\sqrt{81}-1/2\sqrt{16}`

`=2/3 . 9 -1/2 .4`

`=6-2`

`=4`

`4)`

`1/2\sqrt{4/9}-2/5\sqrt{25/16}`

`=1/2 . 2/3 - 2/5 . 5/4`

`=1/3 -1/2`

`=-1/6`

`5)`

`3/2\sqrt{4/9}+\sqrt{16}`

`=3/2 . 2/3 + 4`

`=1+4`

`=5`

`6)`

`1/3\sqrt{81}+4/7\sqrt{49}`

`=1/3 . 9 + 4/7 . 7`

`=3+4`

`=7`