a,=11/12 x 8/15 - 1/6:2

  = 22/45-1/2

  = 73/180

b, =9/4:0.01 

   = 225

K nha

0,25 x 40

= 10

....

Cái chỗ phần b là ( 2 và 1/4 - 0,25 ) :0,01 phần 0,25x 40 nhé mn

1. \(x-8+32=68\)

\(x-8=68-32\)

\(x-8=36\)

\(x=36+8\)

\(x=44\)

_____

2. \(x+8+32=68\)

\(x+8=68-32\)

\(x+8=36\)

\(x=36-8\)

\(x=28\)

_____

3. \(98-x+34=43\)

\(98-x=43-34\)

\(98-x=9\)

\(x=98-9\)

\(x=89\)

_____

4. \(98+x-34=43\)

\(98+x=43+34\)

\(98+x=77\)

\(x=77-98\)

\(x=-21\)

_____

5. \(x:5:4=800\)

\(x:5=800.4\)

\(x:5=3200\)

\(x=3200.5\)

\(x=16000\)

_____

6. \(18+x=384:8\)

\(18+x=48\)

\(x=48-18\)

\(x=30\)

_____

7. \(\left(84,6-2\times x\right):3,02=5,1\)

\(84,6-2.x=5,1.3,02\)

\(84,6-2.x=15,402\)

\(2.x=84,6-15,402\)

\(2.x=69,198\)

\(x=69,198:2\)

\(x=34,599\)

_____

8. \(x\times5=120:6\)

\(x.5=20\)

\(x=20:5\)

\(x=4\)

_____

9. \(\left(15\times24-x\right):0,25=100:0,25\)

\(\left(15.24-x\right):0,25=400\)

\(15.24-x=400.0,25\)

\(15.24-x=100\)

\(360-x=100\)

\(x=360-100\)

\(x=260\)

1,x-8+32=68

=>x-8=68-32=36

=>x=36+8=42

2,x+8+32=68

=>x+8=68-32=36

=>x=36-8=28

3,98-x+34=43

=>98-x=43-34=9

=>x=98-9=89

4,98+x-34=43

=>98+x=43+34=77

=>x=77-98=-21

5,x:5:4=800

=>x:20=800

=>x=800x20=16000

6,18+x=384:8=48

=>x=48-18=30

7,(84,6-2x):3,02=5,1

=>84,6-2x=5,1x3,02=15,402

=>2x=84,6-15,402=69,198

=>x=69,198:2=34,599

8,5x=120:6=20

=>x=20:5=4

9,(15x24-x):0,25=100:0,25=400

=>360-x=400x0,25=100

=>x=360-100=260.

1. \(...\Rightarrow x+24=68\Rightarrow x=68-24=44\)

2. \(...\Rightarrow x+40=68\Rightarrow x=68-40=28\)

3. \(...\Rightarrow3^{2\left(8+x\right)}=9=3^2\Rightarrow2\left(8+x\right)=2\Rightarrow8+x=1\Rightarrow x=-7\)

4. \(...\Rightarrow3^{2\left(8+x\right)}=77\) (bạn xem lại đề)

5. \(...\Rightarrow x:5=800.4\Rightarrow x:5=3200\Rightarrow x=3200.5=16000\)

6. \(...\Rightarrow18+x=48\Rightarrow x=48-18=30\)

7. \(...\Rightarrow84,6-2x=5,1.3,02=15,402\Rightarrow2x=84,6-15,402\Rightarrow2x=69,198\Rightarrow x=34,599\)

8. \(...\Rightarrow5.x=20\Rightarrow x=20:5=4\)

9. \(\left(360-x\right):0,25=400\Rightarrow360-x=400.0,25=100\Rightarrow x=400-100=300\)

a. -25

b. 0,25

a . ( 2,75 + 125% ) x 5/2 - 0,4 x 2 : 8%                           b . ( 1/3 - 25% ) : 50% + ( 1/3 + 0,25 ) x 1/7

  = ( 2,75 + 1,25 ) x 2,5 - 0,4 x 2 : 0,08                             = ( 1/3 - 1/4 ) : 1/2 + ( 1/3 + 1/4 ) x 1/7

  = 4 x 2,5 - 0,4 x 2 : 0,8                                                   = 1/12 : 1/2 + 1/12 x 1/7

  = 10 - 0,8 : 0,8                                                                = 1/12 x 2 + 1/12 x 1/7

  = 10 - 1                                                                           = 1/12 x ( 2 + 1/7 )

  = 9                                                                                  = 1/12 x 15/7 = 5/28

a: \(0.4\cdot\sqrt{0.25-\sqrt{\dfrac{1}{4}}}=0.4\cdot\sqrt{0.25-0.5}\)(đề này sai rồi bạn)

b: \(\dfrac{3}{2}+2\left(x-1\right)=-5\dfrac{1}{2}\)

\(\Leftrightarrow2\left(x-1\right)=\dfrac{-11}{2}-\dfrac{3}{2}=-7\)

\(\Leftrightarrow x-1=\dfrac{-7}{2}\)

hay \(x=-\dfrac{5}{2}\)

Bài 1:

    \(\left(-0,125\right)\times7,9\times80\)

\(=\left(-0,9875\right)\times80\)

\(=79.\)

    \(\left(0,125\right)\times1\times0,25\times8\times\left(-4\right)\)

\(=0,125\times0,25\times8\times\left(-4\right)\)

\(=0,03125\times8\times\left(-4\right)\)

\(=0,25\times\left(-4\right)\)

\(=\left(-1\right).\)

Bài 2:

\(x+\frac{8}{3}^2=\frac{1}{9}\)

\(x+16=\frac{1}{9}\)

           \(x=\frac{1}{9}-16.MSC=9\)

           \(x=\frac{1}{9}-\frac{144}{9}\)

           \(x=\frac{-143}{9}.\)

a) 0,25x3/4-0,25x0,25+0,25x1/2

=0,25x(3/4-0,25+1/2)

=0,25x1

=0,25

b) 5,68x8+56,8x0,1+56,8:10

=5,68x8+5,68+5,68

=5,68x(8+1+1)

=5,68x10

=56,8

a) 0,25x3/4-0,25x0,25+0,25x1/2

=0,25x(3/4-0,25+1/2)

=0,25x1

=0,25

b) 5,68x8+56,8x0,1+56,8:10

=5,68x8+5,68+5,68

=5,68x(8+1+1)

=5,68x10

a) 1/5 x 19 x 2/3 x 10 x 1/2 x 3 x 1/38

= ( 1/5 x 10 ) x ( 19 x 1/38 ) x ( 2/3 x 1/2 ) x 3

= ( 2 x 1/2 )  x ( 1/3 x 3 )

= 1 x 1

= 1

b) 5/8 x 4 x 8/5 x 7 x 0,25 x 1/8

= ( 5/8 x 8/5 ) x (4 x 0,25 ) x ( 7 x 1/8 )

= 1 x 1 x 7/8

= 7/8

a, \(\dfrac{3}{4}x=-\dfrac{9}{8}\)
x= \(-\dfrac{3}{2}\)
b, |x| + 0,25= 5,25
|x | = 5
=> x\(\in\){ +- 5}
Ko chắc đúng, kiểm tra trc khi làm

\(\dfrac{2x-1}{3}=\dfrac{-5}{0.6}\)

\(\Leftrightarrow2x-1=-25\)

hay x=-12

Bài này là dễ lắm rồi đó, bạn tự làm đi

Đẽ ko tưởng tượng nổi đồ óc chó

(15x 19 - x - 0,15 ) : 0,25 = 15 : 0,25 

( 285 - x - 0,15) x 4 = 15 x 4 

(285 -x - 0,15 ) x 4 = 60 

285 - 0,15 - x = 60 : 4 

285 - 0,15 -x = 15

284,85 - x = 15

               x= 284,85 - 15 

               x= 269,85