a. `17.85+15.17-120`
`=17 . (85+15)-120`
`=17 . 100-120`
`=1700-120`
`=1580`
b. `5.7^2 - 24 : 2^3`
`=5. 49 - 24: 8`
`=245-3`
`=242`
c. `3^3 .22 -27.19`
`=27.22 - 27.19`
`=27 . (22-19)`
`=27.3=81`
a. 17.85 + 15.17 - 120
=17(85+15)-120
=17.100-120
=1700-120
=1580
b. 5.72 - 24:23
=5.49-24:8
=245-3
=242
c. 33.22 - 27.19
=27.22-27.19
=27(22-19)
=81