ai k mình mình k lại

ai k mình mình k lại

1/10000 + 13/10000 + 25/10000 + 133/10000 = (1 + 13 + 25 + 133)/10000

                                                                  = 172/10000 = 43/2500

úm ba la xin tích  

12

số cuối trừ số đầu chia khoảng cách cộng 1

Bài làm:

\(\frac{1}{10000}+\frac{13}{10000}+\frac{25}{10000}+...+\frac{133}{10000}\)

\(=\frac{1+13+25+...+133}{10000}\)

\(=\frac{\left(133+1\right)\times\left[\left(133-1\right)\div\left(13-1\right)+1\right]}{10000\times2}\)

\(=\frac{134\times12}{20000}=\frac{201}{2500}\)

\(\frac{1}{10000}+\frac{13}{10000}+\frac{25}{10000}+...+\frac{133}{10000}\)

\(=\frac{1+13+25+...+133}{10000}\)

\(=\frac{\left(133+1\right)\times\left[\left(133-1\right)\div12+1\right]\div2}{10000}\)

\(=\frac{134\times12\div2}{10000}\)

\(=\frac{804}{10000}\)

\(=\frac{201}{2500}\)

Học tốt 

a) 20 × 190 × 50 = (20 × 50) × 190 = 1000 × 190

= 190000

b) (900 × 28) ÷ 9 = (900 ÷ 9) × 28 = 100 × 28 = 2800

` 10000 – 47 xx 72 – 47 xx 28 `
`=10000-47xx(72+28)`
`=10000-47xx100`
`=100xx100-47xx100`
`=100xx(100-47)`
`=100xx53`
`=5300`

`10 000 - 47 xx 72 - 47xx28`

`=10 000 - 47 xx(72+28)`

`=10 000 - 47xx100`

`=10 000 - 4700`

`=5300`

 10000 – 47 x 72 + 47 x 28 

=10000-(47x(72+28)

=10000-4700

=5300

7 x 450 - 900 + 450 x 5

= 7 x 450 - 450 x 2 + 450 x 5

= 450 x (7 - 2 + 5)

= 450 x 10

= 4500

   7 x 450 - 900 + 450  x 5

= 450  x 7 +  450 x 5 - 450 x 2

= 450 x (7 + 5 - 2)

= 450 x (12 - 2)

= 450 x 10

= 4500

7 x 450 - 900 + 450 x 5

= 7 x 450 - 450 x 2 + 450 x 5

= 450 x (7 - 2 + 5)

= 450 x 10

= 4500

bằng 0

 (128,36×0,25+128,36×0,75)×(11×9-900×0,1-9)

=(128,36×0,25+128,36×0,75) X  0

=           0

0=nịt