100-20+38- 15
Tính:
a/ 48 + 25 – 38 = 73 – 38 = 35
b/ 100 - 38 + 15 = 62 + 15 = 77
a/ 48 + 25 – 38 = 73 – 38 = 35
b/ 100 - 38 + 15 = 62 + 15 = 77
1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+149+20+21+22+23+24+25+26+27+28+29+30+31+32+33+34+35+36+37+38+39*100
tính bằng cách thuận tiện nhất 35*18-9*70*100
15+15*2+7*5-100
62-52+37+28-38+63
107-{38+[7*9-20/5+(19+11)]}/15
1) -145.(13 - 57) + 57.(10 -145)
2) 17.(15 - 16) + 16.( 17- 20)
3) -38.(25 - 4) + 25.(-4 + 38 )
4) 23.(145 - 17) - 145.(23 - 6)
5) 24.(15 - 4) + 4.(24 - 15)
6) 199.(15 - 17) - 199.(-17 + 5)
7) -39.(5 - 99) + 99.(10 - 39)
1: \(=-145\cdot13+145\cdot57+57\cdot10-57\cdot145=-1315\)
2: \(=17\cdot15-17\cdot16+16\cdot17-16\cdot20=255-320=-65\)
3: \(=-38\cdot25+38\cdot4-25\cdot4+25\cdot38=13\cdot4=52\)
4: \(=23\cdot145-23\cdot17-145\cdot23+145\cdot6=479\)
5: \(=24\cdot15-24\cdot4+4\cdot24-4\cdot15=360-60=300\)
6: \(=199\left(15-17+17-5\right)=199\cdot10=1990\)
7: \(=-39\cdot5+39\cdot99+99\cdot10-99\cdot39=795\)
1: =−145⋅13+145⋅57+57⋅10−57⋅145=−1315=−145⋅13+145⋅57+57⋅10−57⋅145=−1315
2: =17⋅15−17⋅16+16⋅17−16⋅20=255−320=−65=17⋅15−17⋅16+16⋅17−16⋅20=255−320=−65
3: =−38⋅25+38⋅4−25⋅4+25⋅38=13⋅4=52=−38⋅25+38⋅4−25⋅4+25⋅38=13⋅4=52
4: =23⋅145−23⋅17−145⋅23+145⋅6=479=23⋅145−23⋅17−145⋅23+145⋅6=479
5: =24⋅15−24⋅4+4⋅24−4⋅15=360−60=300=24⋅15−24⋅4+4⋅24−4⋅15=360−60=300
6: =199(15−17+17−5)=199⋅10=1990=199(15−17+17−5)=199⋅10=1990
7: =−39⋅5+39⋅99+99⋅10−99⋅39=795
Tính hợp lí
1) -145.(13 - 57) + 57.(10 -145)
2) 17.(15 - 16) + 16.( 17- 20)
3) -38.(25 - 4) + 25.(-4 + 38 )
4) 23.(145 - 17) - 145.(23 - 6)
5) 24.(15 - 4) + 4.(24 - 15)
6) 199.(15 - 17) - 199.(-17 + 5)
7) -39.(5 - 99) + 99.(10 - 39)
35 + 36 + 37 + 38 + 39 + 40 - 20 - 19 - 18 - 17 - 16 - 15
35 + 36 + 37 + 38 + 39 + 40 - 20 - 19 - 18 - 17 - 16 - 15=?
=120
hok tốt !
= (35 - 15) + (36 - 16) + (37 - 17) + (38 - 18) + (39 - 19) + (40 - 20)
=20 + 20 + 20 + 20 + 20 +20
=120
ok ?
1. -2/9 x 15/17 + -2/9 x 2/17
2. -5/3 x 6/5 + -7/9 x 3/10
3. 15/20 x 7/5 + -9/7 x -6/4
4.-25/13 x 5/19 + -25/13 x 14/19
5 -7/13 x 13/5 + -9/7 x 5/3
6. 27/35 x 5/9 - 2/7 x -7/5
7. 10/13 x 13/5 + {-9/5} x 10/3
8. 100/27 x 9/20 + 40% x 5/3
9. 1,5 x 5/12 + 1/4 x 3/4
10. 2 1/2 x 7/5 + {-9/10} x 2/3
11. X + 45% = 2 1/2 -5/3
12. 80% + X = -5/2 + 3/4
13. 4/25 - X =-5/2 + -3/10
1: =-2/9(15/17+2/17)=-2/9
2: \(=\dfrac{-6}{3}+\dfrac{-21}{90}\)
=-2-7/30=-67/30
3: \(=\dfrac{3}{4}\cdot\dfrac{7}{5}+\dfrac{9}{7}\cdot\dfrac{3}{2}\)
=21/20+27/14=417/140
4: =-25/13(5/19+14/19)=-25/13
5: =-7/5-45/21=-7/5-15/7=-124/35
1: =-2/9(15/17+2/17)=-2/9
2: =34⋅75+97⋅32=34⋅75+97⋅32
=21/20+27/14=417/140
4: =-25/13(5/19+14/19)=-25/13
5: =-7/5-45/21=-7/5-15/7=-124/35
-145 (13-57) + 57(10-145)
17(15-16) + 16(17-20)
-38(25-4)+25(-4+38)
Tính hợp lý giúp mình vs ạ,mình cảm ơn mn nhiều