Khái niệm số thập phân

1/10=0.1

5/10=0.5

1/10 = 0,1

5/ 10 = 1/2 = 0,5

1/10 = 0,1

5/10=1/2=0,5

\(\dfrac{12}{100}\)

0,15 nha

\(\dfrac{12}{100}\)

`648-x xx 34 =444`

`x xx 34=648-444`

`x xx 34=204`

`x=204:34`

`x=6`

$648-x\times 34=444$

$x\times 34=648-444$

$x\times 34=204$

$x=204:34$

$x=6$

\(a,94dm\)

\(b,350kg\)

\(c,324cm\)

\(d,4300mm\)

\(e,4240m\)

\(g,32250\)

a,94

b,350

c,324

d,4300

e,4240

g,32250

a:94 

b:350

c:324

d:4300

e:4240

g:32250

45,82

=45,82

= 45,82

21

=21

21

<

72

765

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\(\dfrac{1}{1000}+\dfrac{13}{1000}+\dfrac{25}{1000}+...+\dfrac{109}{1000}\)

\(=\dfrac{1+13+25+...+109}{1000}\)

\(=\dfrac{\left(109+1\right)\times10:2}{1000}\)

\(=\dfrac{500}{1000}=\dfrac{1}{2}\)

a) \(\dfrac{13}{5}=2,6\)

\(\dfrac{4}{25}=0,16\)

\(\dfrac{3}{4}=0,75\)

b) \(\dfrac{75}{100}=\dfrac{3}{4}=0,75\)

\(\dfrac{102}{600}=\dfrac{17}{100}=0,17\)

\(\dfrac{62}{125}=0,496\)

13/5 -> 26/10 -> 2,6

4/25 -> 16/100 -> 0,16

3/4 -> 75/100 -> 0,75

75/500 -> 15/100 -> 0,15

102/600 -> 17/100 -> 0,17

62/125 -> 496/1000 -> 0,496

a/

\(\dfrac{13}{5}=\dfrac{26}{10}=2,6\\ \dfrac{4}{25}=\dfrac{16}{100}=0,16\\ \dfrac{3}{4}=\dfrac{75}{100}=0,75\)

b/

\(\dfrac{75}{500}=\dfrac{15}{100}=0,15\\ \dfrac{102}{600}=\dfrac{17}{100}=0,17\\ \dfrac{62}{125}=\dfrac{496}{1000}=0,496\)

các phân số thập phân là

\(\dfrac{41}{100};\dfrac{2}{10};\dfrac{3}{1000};\dfrac{7}{700}=\dfrac{1}{100}\)