a,1/2*5/4+1/2*3/4+1/2
b,72/95*64/72*95/72*14/86*72/64*86/14
Tính thuận tiện,đây là *nhân nha
a, 86 + 375 +14 ;
b, 72 + 69 + 128 ;
c, 25 . 5 . 4 . 27 . 2 ;
d, 28 . 64 + 28 . 36 ;
a) \(86+375+14\)
\(=\left(86+14\right)+375\)
\(=100+375\)
\(=475\)
b) \(72+69+128\)
\(=\left(72+128\right)+69\)
\(=200+69\)
\(=269\)
c) \(25\cdot5\cdot4\cdot27\cdot2\)
\(=\left(25\cdot4\right)\cdot\left(5\cdot27\right)\cdot2\)
\(=100\cdot135\cdot20\)
\(=200\cdot135\)
\(=27000\)
d) \(28\cdot64+28\cdot36\)
\(=28\cdot\left(64+36\right)\)
\(=28\cdot100\)
\(=2800\)
a, 86+375+14
=(86+14)+375
=100+375
=475
b, 72+69+128
=(72+128)+69
=200+69
=269
c, 25.5.4.27.2
=(25.4)(5.2).27
=100.10.27
=1000.27
=27000
d, 28.64+28.36
=28(64+36)
=28.100
=2800
tính bằng cách thuận tiện nhất:
a.55 * 72 + 43 * 72 + 2 * 72
b.64 * 98+64+64
kb nha
đúng mình tick
hy?mik hỏi nềk ? cs ai bt eff hôn eff hộ mềnh nka , gửi anhr shau! code oc : ||||uwuHARU_ko|white||vn|||200|39|72|5|11|9|1|0|1|0|1|1|95|98|20|0|0|72|72|1|1|58|58|53|0|57|92|88|0|7|7|56|6|6|0|86|86|22|22|82|82|77|77|55|95|0|0|34|34|35|1|80|0|0|0|21|21|0|0|1|1|0|2|2|2|6|0|11|11|1|7|1|17|6|1|1|1|1|1|1|0|0|0|6|0|5|1|0|1|1|1|1|0|0|0|0|0|0|-1|8|12|-6|0|-1|8|12|6|-4|0|18|10|0|4|0|18|10|0|1|12|11|14|-3|-1|12|11|14|3|12|-3|11|18|0|4|-8|5|12|21|4|4|4|19|0|3|70|17|17|324|0|-4|3|19|0|-8|8|1|15|0|-4|-10|2|12|0|-50|34|12|12|18|-16|-12|9|12|0|0|-2|1|12|0|-7|-9|4|12|0|1|15|3|20|16|0|0|2|16|12|342|1|3|1|3|3|4|6|6|1|1|21|1|357|1|1|0|0|1|1|0|1|1|1|1|1|1|1|1|1|1|1|1|1|1|1|1|1|327|-219|0|1|1|11|1|0|0|18|20|3|10|84|20|18|180|2|2|0|-10|0|0|0|0|0|1|1|1|0|0|-2|-10|14|44|0|0|0|0|FFF3E7|D00447|EEC07A|874C12|EEC07A|EEC07A|874C12|EEC07A|EEC07A|874C12|EEC07A|EEC07A|874C12|EEC07A|BB9178|8A624F|BB9178|24214D|FFFFFF|A19E78|A19E78|27170F|A19E78|A19E78|27170F|FFFFFF|FFFFFF|FFFFFF|FFFFFF|4F513A|4F513A|4F513A|4F513A|191919|020202|ECECEC|191919|020202|191919|FF3F3F|020202|FF3F3F|FFDEC4|FFDEC4|FFDEC4|FF3F3F|020202|FFFFFF|FFFFFF|FF8383|A30337|FFFFFF|71AA6D|3B5838|71AA6D|B4BFCD|2F3848|B4BFCD|FFFFFF|AA657F|FFFFFF|191919|FFFFFF|DBB0B0|FFFFFF|CB8DA8|FFDBEF|FFFFFF|020202|191919|8AAEFF|00132C|FFFFFF|8AAEFF|00132C|8AAEFF|8AAEFF|00132C|8AAEFF|FFFFFF|8C4A4A|FFFFFF|FFFFFF|ECECEC|FFFFFF|191919|020202|191919|191919|020202|191919|FFFFFF|00232C|FFFFFF|191919|020202|191919|FFFFFF|646D7B|FFFFFF|FFFFFF|646D7B|FFFFFF|FFFFFF|00132C|8AAEFF|FFFFFF|00132C|8AAEFF|7B7B7B|020202|2F3848|7B7B7B|020202|2F3848|D00447|720226|FFFFFF|8AAEFF|00132C|8AAEFF|8AAEFF|00132C|FFFFFF|FFFFFF|020202|A487FF|FFFFFF|020202|A487FF|AAA7CB|08016D|AAA7CB|333333|191919|FFFFFF|FF3F3F|020202|FFFFFF|FF3F3F|020202|191919|8589FF|020202|FFFFFF|8589FF|020202|FFFFFF|191919|020202|B4BFCD|FFFFFF|93A1B1|FFFFFF|020202|8C4A4A|020202|FFFFFF|020202|FFFFFF|020202|CB8989|FFFFFF|CB8989|020202|020202
Aps dụng các tính chất của phép cộng và phép nhân để tính nhanh:
a) 86 + 357 + 14 ; b) 72 + 69 + 128;
c) 25 . 5 . 4 . 27 . 2; d) 28 . 64 + 28 . 36
a 86+14+357=100+357=457
b 72+128+69=200+69=269
c (25.4).(5.2).4.27
=100.10.4.27
=1000.4.27
=4000.27=64000
d 28. (64+36)=28.100=2800
nha
a) 86 + 357 + 14 b ) 72 + 69 +128
= ( 86 + 14 ) + 357 = ( 72 + 128 ) + 69
= 100 + 357 = 200 + 69 = 269
= 457
c) 25 . 5 . 4 . 27 .2
= ( 25.4).(5.2).27
= 100 x 10 x 27
= 1000 x 27
= 27 000
d) 28.64+28.36
= 28 . ( 64 + 36 )
= 28.100
= 2800
a) 86 + 357 + 14
= ( 86 + 14 )+ 357
= 100 + 357
= 457
b) 72 + 69 + 128
= ( 72 + 128 ) + 69
= 200 + 69
= 269
c) 25 . 5 . 4 . 27 . 2
= ( 25 . 4 ) . ( 5 . 2 ) . 27
= 100 . 10 . 27
= 1000 . 27
= 27000
Bài 7: Tính bằng cách thuận tiện nhất
a) (25x32) : 8 b) 24 x 11 + 6 x 86 x 4 + 72
c) 36 x 5 + 9 x 79 x 4 + 72 x 8 d) (56x125) : 7
a) (25x32) : 8
= 25 x (4 x 8) : 8
= (25 x 4) x (8:8)
= 100 x 1
=100
b, 24 x 11 + 6 x 86 x 4 + 72
= 24 x 11 + (6 x 4) x 86 + 24 x 3
= 24 x 11 + 24 x 86 + 24 x 3
= 24 x (11+86+3)
= 24 x 100
= 2 400
\(\left(25\times32\right):8=25\times32:8=25\times\left(32:8\right)=25\times4=100\\ 24\times11+6\times86\times4+72\\ =24\times11+24\times86+24\times3\\ =24\times\left(11+86+3\right)\\ =24\times100=2400\\ 36\times5+9\times79\times4+72\times8\\ =36\times5+36\times79+36\times16\\ =36\times\left(5+79+16\right)\\ =36\times100=3600\\ \left(56\times125\right):7=56\times125:7=\left(56:7\right)\times125=8\times125=1000\)
a=457
b=269
d=57
còn câu C ko có phép tính nên mình ko làm
a) 86+357+14=(86+14)+357=100+357=457
b) 72+69+128=(72+128)+69=200+69=269
c) 25.5.4.27.2=(25.4).(5.2).27=100.10.27=27000
d) 28.64+28.36=28.(64+36)=28.100=2800
Tomoyo Daidouji à phép nhân á bạn . 25 nhân 5 nhân 4 nhân 27 nhân 2
Tính nhẩm:
a) 27 × 10 = …...; 72 × 100 =…...; 14 × 1000 =…...
86 × 10 = …...; 103 × 10 =…...; 452 × 1000 =…...
358 × 10 = …...; 1977 × 100 =…...; 300 × 1000 =…...
b) 80 : 10 = …...; 400 : 100 =…... ;6000 : 1000 =…...
300 : 10 = …...; 4000 : 100 =…... ;60000 : 1000 =…...
2000 : 10 =…...; 40000 : 100 =…... ;600000 : 1000 =…...
c) 64 × 10 =…...; 32 × 100 =…...; 95 × 1000 =…...
640 : 10 =…...; 3200 : 100 =…...; 95000 : 1000 =…...
a) 27 × 10 = 270; 72 × 100 = 7200; 14 × 1000 = 14000
86 × 10 = 860; 103 × 10 = 10300; 452 × 1000 = 452000
358 × 10 = 3580; 1977 × 100 = 197700; 300 × 1000 = 300000
b) 80 :10 = 8; 400 : 100 = 4 ;6000 : 1000 = 6
300 : 10 = 30; 4000 : 100 = 40 ; 60000 : 1000 = 60
2000 :10 = 200; 40000 :100 = 400 ;600000 : 1000 = 600
c) 64 × 10 = 640; 32 × 100 = 3200; 95 × 1000 = 95000
640 : 10 = 64; 3200 : 100 = 32; 95000 : 1000 = 95
ap dung cac tinh chat cua phep cong va phep nhan de tinh nhanh
86+357+14
72+69+128
25*5*4*27*2
28*64+28*36
\(86+357+14=457\)
\(72+69+128=275\)
\(25\cdot5\cdot4\cdot27\cdot2=27000\)
\(28\cdot64+28\cdot36=28\left(64+36\right)=2800\)
a) \(86+357+14=\left(86+14\right)+357=100+357=457\)
b) \(72+69+128=\left(72+128\right)+69=200+69=269\)
c) \(25.5.4.27.2=\left(25.4\right).\left(5.2\right).27=100.10.27=27000\)
d) \(28.64+28.36=28\left(64+36\right)=28.100=2800\)
Điền dấu >, <, = vào chố chấm:
28 … 31 | 84 … 90 | 54 … 50 + 5 |
65 … 64 | 72 … 72 | 25 … 20 + 5 |
23 … 32 | 48 … 39 | 86 … 80 + 7 |
Lời giải chi tiết:
28 < 31 | 84 < 90 | 54 < 50 + 5 |
65 > 64 | 72 = 72 | 25 = 20 + 5 |
23 < 32 | 48 > 39 | 86 < 80 + 7 |
28 < 31 | 84 < 90 | 54 < 50 + 5 |
65 > 64 | 72 = 72 | 25 = 20 + 5 |
23 < 32 | 48 > 39 | 86 < 80 + 7 |