1.d

2.b

d c

D và c

\(\frac{8.15.42}{16.21.45}=\frac{8.15.21.2}{8.2.21.15.3}=\frac{1}{3}\)

\(\frac{25.33.60.7}{21.65.121.48}=\frac{5.5.11.2.12.5.7}{7.3.13.5.11.12.12.4}=\frac{25}{572}\)

Đề : Em muốn tham gia học ngoại khóa môn bơi lội  ở nhà văn hóa thiếu nhi tiinhr đồng nai. Em hãy viết lá đơn xin tham gia khóa học đó

làm hộ mình nhé 

\(\frac{8\cdot15\cdot42}{16\cdot21\cdot45}=\frac{8\cdot15\cdot21\cdot2}{2\cdot8\cdot21\cdot15\cdot3}=\frac{1}{3}\)

\(\frac{25\cdot33\cdot60\cdot7}{21\cdot65\cdot121\cdot48}=\frac{5\cdot5\cdot3\cdot11\cdot12\cdot5\cdot7}{3\cdot7\cdot13\cdot5\cdot11\cdot11\cdot12\cdot4}=\frac{5\cdot5}{13\cdot11\cdot4}=\frac{25}{572}\)

25 x 33 + 25 x 87 + 64 x 73 + 64 x 47

= 25 x ( 33 + 87 ) + 64 x ( 73 + 47 )

= 25 x 120 + 64 x 120

=  120 x ( 15 + 64 )

= 120 x 49

= 5580

25 x 33 + 25 x 87 + 64 x 73 + 64 x 47

= 25 x ( 33 + 87 ) + 64 x ( 73 +47 )

= 25 x  120 + 64 x 120

= 120 x ( 25 + 64 )

= 120 x 89

= 10680

25 x 33 + 25 x 87 + 64 x 73 + 64 x 47

= ( 33 + 87 ) x 25 + ( 73 + 47 ) x 64

= 120 x 25 + 120 x 64

= ( 25 + 64 ) x 120

= 89 x 120

= 10680

@#$%^&* !

\(40:x+25=33\\ \Rightarrow40:x=8\\ \Rightarrow x=5\)

x=5

 40 : x + 25 = 33 
⇒ 40 : x     = 33 - 25
⇒ 40 : x     = 8
⇒       x      = 40 : 8
⇒         x      = 5​

\(\dfrac{11}{25}\times9\times\dfrac{5}{33}=\dfrac{99}{25}\times\dfrac{5}{33}=\dfrac{3}{5}\)

cảm ơn bn nhìu =)

nhu cai dau buoi dap an la 3/6 yen tam tao hoc sinh lop 12

a,=3/13.17/29.29/34

=3/13.1/2

=3/26

b,=(4/21+25/42).19/33

=11/14.19/33

=19/42

`a, = 3/13 xx (17/29 xx 29/34)`

`= 3/13 xx 1/2`

`= 3/26`.

`b, = 19/33(4/21 + 25/42)`

`= 19/33 xx ( 33/42 )`

`= 19/42`

`a)(3/13xx17/29)xx29/34=3/13xx17/29xx29/34=[3xx17xx29]/[13xx19xx17xx2]=3/26`

`b)4/21xx19/33+25/42xx19/33=19/33xx(4/21+25/42)=19/33xx(8/42+25/42)=19/33xx33/42=19/42`

\(\frac{x+34}{33}+\frac{x+33}{29}+\frac{x}{25}=8\)

\(\frac{725\left(x+34\right)}{23925}+\frac{825\left(x+33\right)}{23925}+\frac{957x}{23925}=\frac{191400}{23925}\)( ko hiểu thì inbox riêng nha )

\(725x+24650+825x+27225+957x=191400\)

\(2507x+51875=191400\)

\(2507x+51875-191400=0\)

\(2507x-139525=0\)

\(2507x=139525\)

\(x=\frac{139525}{2507}\)

\(\dfrac{15}{19}\times\dfrac{25}{33}-\dfrac{15}{19}\times\dfrac{14}{33}\)

\(=\dfrac{15}{19}\times\left(\dfrac{25}{33}-\dfrac{14}{33}\right)\)

\(=\dfrac{15}{19}\times\dfrac{11}{33}\)

\(=\dfrac{5}{19}\)

Lần sau để đúng môn học nha bạn.

Thế có biết câu hỏi này ko

2300x10=?

313×1729)×2934(313×1729)×2934

=313×1729×2934=313×1729×2934

=3×17×2913×29×34=3×17×2913×29×34

=3×17×2913×29×2×17=3×17×2913×29×2×17

=313×2=313×2

=326=326

421×1933+2542×1933421×1933+2542×1933

=1933×(421+2542)=1933×(421+2542)

=1933×(842+2542)=1933×(842+2542)

=1933×3342=1933×3342

=19×3333×42=19×3333×42

=1942