\(13\frac{2}{5}-\left(\frac{18}{23}-2\frac{6}{16}\right)\)

\(=13\frac{2}{5}-\frac{18}{23}+2\frac{6}{16}\)

\(=\frac{67}{5}-\frac{18}{23}+\frac{38}{16}\)

Tính tiếp nha

`a)3/5+(-4/9)`

`=3/5-4/9`

`=27/45-20/45`

`=7/45`

`b)3/5+2/5 . 15/8`

`=3/5 + 30/40`

`=3/5+3/4`

`=12/20+15/20`

`=27/20`

`c)7/2 . 8/13 + 8/13 . (-5/2)`

`=8/13 . (7/2 +(-5)/2)`

`=8/13 . 1`

`=8/13`

`d)-5/17 . (-9/23)+9/23 . (-22/17) + 11 9/23`

`=-5/17 . (-9/23) + 9/23 . (-1) . 22/17 + 11 + 9/23`

`=-5/17 . (-9/23) + (-9/23) . 22/17+11+9/23`

`= -9/23 ( -5/17 + 22/17)+11+9/23`

`= - 9/23 . 1+11+9/23`

`=-9/23+11+9/23`

`=(-9/23+9/23)+11`

`=0+11`

`=11`

a: =27/45-20/45=7/45

b: =3/5+30/40

=3/5+3/4

=12/20+15/20

=27/20

c: =8/13(7/2-5/2+1)=8/13*2=16/13

d: =9/23*5/17-9/23*22/17+11+9/23

=-9/23+11+9/23

=11

a, 64 . 23 + 37 . 23  - 23 

= 23. (64 + 37  - 1) 

= 23 . 100

=2300 

b, 33,76 + 19,52 + 6,24 

= (33,76 + 6,24) + 19,52 

= 40 + 19,52 

= 59,52 

c, 38/11 + (16/13 + 6/11) 

 = 38/11 + 16/13 + 6/11 

= (38/11 + 6/11) + 16/13 

= 4 + 16/13 

= 52/13 + 16/13 

= 68/13 

d, 3/4 : 3/5 - 1/5 

= 3/4 . 5/3 - 1/5 

= 5/4 - 1/5 

= 25/20 - 4/20 

= 21/20

e, \(5\frac{3}{4}\div\frac{12}{13}+6\frac{1}{4}\div\frac{12}{13}\)

\(=\frac{23}{4}\cdot\frac{13}{12}+\frac{25}{4}\cdot\frac{13}{12}\)

\(=\frac{13}{12}\cdot\left(\frac{23}{4}+\frac{25}{4}\right)\)

\(=\frac{13}{12}\cdot12=13\)

f, S = 1 + 2 + 3 + 4 + ... + 99 + 100 

Số số hạng của S là : 

(100 - 1) : 1 + 1 = 100 (số hạng) 

Tổng của S là : 

(1 + 100) . 100 : 2 = 5050

Vậy S = 5050 

Dấu " . " là dấu nhân nhé :D 

lộn xộn quá cậu viết lại qua kí tự " gõ công thức toán đi"

Mk gõ lại cho

\(\left(\frac{173535}{88375}-\frac{161001}{1365}\right)x3\frac{6}{23}:\left(5-1\frac{187}{253}\right)\)

Bài 1:

a) \(2\frac{1}{4}+1\frac{1}{2}-1\frac{4}{5}\)

=\(\frac{9}{4}\)+\(\frac{3}{2}\)-\(\frac{9}{5}\)

=\(\frac{45}{20}+\frac{30}{20}-\frac{36}{20}\)

=\(\frac{39}{20}\)

b) \(2\frac{2}{3}\times3\frac{1}{4}:2\frac{3}{4}\)

\(\frac{8}{3}\times\frac{13}{4}:\frac{11}{4}\)

=\(\frac{8}{3}\times\frac{13}{4}\times\frac{4}{11}\)

=\(\frac{104}{33}\)

Bài 2:

a) \(\frac{7}{9}+\frac{4}{5}+\frac{11}{9}+\frac{6}{5}\)

=\(\left(\frac{7}{9}+\frac{11}{9}\right)+\left(\frac{4}{5}+\frac{6}{5}\right)\)

=2+2

=4

b) \(\frac{21}{36}\times\frac{39}{14}\times\frac{54}{13}\)

=\(\frac{21\times39\times54}{36\times14\times13}\)

=\(\frac{675}{100}\)

dung ko ban

i don'n know