`1a)``(12,48:0,5xx6,25xx4xx2 )/(2xx3,12xx1,25:0,25xx10)`
`=(12,45xx2xx6,25xx4xx2)/(2xx3,12xx1,25xx4xx10)`
`=(12,45xx\cancel(2)xx6,25xxcancel(4)xx2)/(cancel(2)xx3,12xx1,25xxcancel(4)xx10`
`=(12,45xx6,25xx2)/(3,12xx1,25xx10)`
`=(cancel(12,45)xx4xxcancel(6,25)xx5xx2)/(cancel(3,12)xxcancel(1,25)xx10`
`=(4xx5xx2)/10`
`=40/10=4`
`b)``(16xx25-25xx7)/(153+15xx3)`
`=(25xx(16-7))/(51xx3+15xx3)`
`=(25xx9)/(3xx(51+15))`
`=(25xx9)/(3xx66)`
`=(25xxcancel(9))/(22xxcancel(9))`
`=25/22`
`2`
Thể tích bể là:
`4xx3xx1,8=21,6m^3`
Thể tích nước là:
`21,6xx80%=17,28m^3=17280l`
Chiều cao mực nước là:
`17,28:4:3=1,44(m)`
Vậy bể có `17280` lít nước và cao `1,44m`.