Bài 1. Tính:
1/ 12.18 + 14.3 - 255 : 17 2/ 68 + 42,5 - 625 : 25 3/ 13 + 21.5 - (198: 11 - 8) 4/ 272 : 16 - 5 + 4 (30 - 5 - 255 : 17) 5/ 25.8 - 12.5 + 272 : 17-8 6/ 125 : 25 + 14 - 142 : 71 7/ 13.17 - 256 : 16 + 14 : 7-1 8/ 15.24 - 14.5 (145 : 5 - 27) 9/ 289 : 17 - 324 : 18 + 18:3 10/ 18.3 - 182 + 3 (51 : 17) | 11/ (64 + 115 + 36) - 25.8 12/ 15.8 - (17 – 30 + 83) - 144 : 6 13/ 19 + 19.99 - 25.8 14/ 250 : 50 - (46 - 75 +54): 5 15/ 13 (17 - 95 + 83): 5 - 18:9 16/ 140 - 180 (47 – 90 + 43) + 7 17/ 24 (15 + 30 + 85 - 120): 10 18/ 27 + 73 – 30 : (25 - 10) 19/ 18 - 4 (27 - 90 + 73): 10 20/ 15 – 25.8 : (100.2) |
1.Tính
1. 12.18+14.3-255:17=216+42-15
=258-15
=243
2. 68+42.5-625:25=68+210-25
=278-25
=253
3. 13+21,5-(198:11-8)=13+105-(108-8)
=13+105-10
=118-10
=108
4. 272:16-5+4(30-5-255:17)=17-5+4.(30-5-15)
=17-5+(25-15)
=17-5+10
=12-10
=2
5. 25.8-12.5+272:17-8=200-60+16-8
=140+16-8
=156-8
=148
6. 125:25+14-142:71=5+14-2
=19-2
=17
7. 13.17-256:16+14:7-1=221-16+2
=205+2
=207
8. 15.24-14.5(145:5-27)=360-70.(29-27)
=360-70.2
=360-140
=220
9/ 289 : 17 - 324 : 18 + 18 : 3
= 17 - 18 + 6
= (-1) + 6
= 5
11/ (64 + 115 + 36) - 25 . 8
= (179 + 36) - 200
= 215 - 200
= 15
14/ 250 : 50 - (46 - 75 + 54) : 5
= 5 - (-29 + 54) : 5
= 5 - 25 : 5
= 5 - 5
= 0
16/ 140 - 180( 47 - 90 + 43) + 7
= 140 - 180( 47 + 43 - 90) +7
= 140 - 180( 90 - 90) +7
= 140 - 180 . 0 + 7
= 140 - 0 + 7
= 147
18/ 27 + 73 - 30 : (25 - 10)
= 100 - 30 : 15
= 100 - 2
= 98
20/ 15 - 25 . 8 : (100 . 2)
= 15 - 200 : 200
= 15 -1
= 14