\(17\cdot85+15\cdot17+2^3\cdot3\cdot5\)

\(=17\cdot100+40\cdot3\)

\(=1700+120=1820\)

17.85 + 15.17 – 120 = 17.(85 + 15) – 120 = 17.100 – 120 = 1700 – 120 = 1580

a,\(5.2^2\)\(-18:3^2\)

\(=5.4-18:9\)

\(=20-2\)

\(=18\)

b, \(\text{17.85+15.17-120}\)

\(=17.\left(85+15\right)\)\(-120\)

= \(17.100-120\)

\(=1700-120\)

\(=1580\)

c, \(2^3\)\(.17-2^3\)\(.14\)

= \(2^3\)\(.\left(17-14\right)\)

\(=8.3\)

\(=24\)

Hok tốt !

5.2²-18:3

Bạn làm sx

17.85 + 15.17 - 120 

= 1445 + 255 -120 

=1700 - 120  

=1580 

a/17.85+15.17-120

=120.[(17-17).(85+15)]

=120.          0

=0

17.85+15.17-120

=[85+15].17-120

=100.17-120

=1700-120

=1480

a) 17. 85 + 15 . 17 = 300

= 17. 9 85 = 15) + 300

= 2000

b) 72. 121 + 27 .121 = 121

= 121 . ( 72 + 27 = 1)

= 12100

c) 32. 39 + 52 . 21 - 12 . 39 + 21 . 48

= ( 32 - 12).39 + 21. ( 52 + 48)

= 2880

d) 47 - ( 45.24 - 52.12) : 14

= 47 - ( 45 . 16 - 25.12) : 14

= 17

e) 102 - 60 : ( 54 : 52 - 3. 5)

= 100 - 60 : ( 25 - 15)

= 100 - 6

= 94

a,  5 . 2 2 - 18 : 3 2

= 5.4 – 18:9

= 20 – 2 = 18

b, 17.85+15.17 – 120

= 1445+255 – 120

= 1580

c,  2 3 . 17 - 2 3 . 14

=  2 3 . ( 17 - 14 ) = 8.3 = 24

d, 20 – [30 –  5 - 1 2 ]

= 20 – (30 – 16) = 6

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 = 1580

b = 242

c = 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

=123+124+125-113-114-115

=(123-113)+ ​(124-114)+ (125-115)

=10+10+10

=30

\(\text{(123+ 124 + 125) – (113 + 114 + 115)}\)

\(=123+124+125-113-114-115\)

\(=\left(123-113\right)+\left(124-114\right)+\left(125-115\right)\)

\(=10+10+10=30.\)

=123+124+125-113-114-115

=(123-113)+ ​(124-114)+ (125-115)

=10+10+10

=30