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)
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:
By Natalia
Đáp án:
Giải thích các bước giải:
1)12 .18 +14.3 -255:17
=216 +42 -15
=243
2) 68 +42.5 -625 :25
=68 +210 -25
=253
3) 13 +21,5 -(198 :11 -8)
=24 ,5 -( 18-8)
=24,5 -10
=14,5
4)272:16 -5 +4.(30 -5 -255 :17)
=17 -5 +4.( 25 -15)
=12 +4.10
=12 +40
=52
5)25 .8 -12.5 +272: 17 -8
=200 -60 +16 -8
=140 +8=148
6)125 :25 +14 -142:71
=5 +14 -2
=17
7)13: 17 -256 :16 +14:7 -1
=13.17 -16 +2 -1
=13 .17 -15
=221 -15
=206
8) 15 .24 -14.5( 145 :5 -27)
=360 -70.(29 -27)
=360 -70.2
=360-140
=220
Đáp án:
1=243
2=253
3=108
4=2
5=148
6=17
7=207
8=220
Giải thích các bước giải:
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