Bài 1:

1. 425x7x4-170x60

= (425x4)x7-170x10x6

=   1700 x7-    1700 x6

=   1700x (7-6)

=   1700x   1

=       1700.

2. 8x9x14+6x17x12+19x4x18

= (8x9)x14+(6x12)x17+(18x4)x19

=   72  x14+   72   x17+   72   x19

=  72x( 14+17+19 )

=  72x     50

=      3600.
 

a = 5400 

b = 81000

c = 7 000 000 

d = 108800 

e = 3600 nhé bạn 

k cho mình nha , cảm ơn nhiều

a,9 x 24 x 25= 5.400

b,12 x125 x54= 81.000

c,64 x 125 x 875 =7.000.000

d,425 x 7 x 4 - 170 x 60=1.700

e,8 x 9 x 14 + 6 x 17 x 12 +19 x 4 x18=3.600

a) \(435-\left(x+16\right)=425:17\)

\(435-\left(x+16\right)=25\)

\(x+16=435-25\)

\(x+16=410\)

\(x=410-16\)

\(x=394\)

b) \(\left(x+\frac{3}{4}\right)\times\frac{7}{4}+\frac{7}{6}=5\)

\(\left(x+\frac{3}{4}\right)\times\frac{7}{4}=5-\frac{7}{6}\)

\(\left(x+\frac{3}{4}\right)\times\frac{7}{4}=\frac{23}{6}\)

\(x+\frac{3}{4}=\frac{23}{6}:\frac{7}{4}\)

\(x+\frac{3}{4}=\frac{46}{21}\)

\(x=\frac{46}{21}-\frac{3}{4}\)

\(x=\frac{121}{84}\)

435 - ( x + 16 ) = 425 : 17

435 - ( x + 16 ) = 25

           x + 16   = 435 - 25

           x + 16   = 410

           x           = 410 - 16

           x           = 394

a) \(435-\left(x+16\right)=425:17\)

\(435-\left(x+16\right)=25\)

\(\Rightarrow x+16=435-25=410\)

\(\Rightarrow x=410-16=394\)

b) \(\left(x+\frac{4}{3}\right)\cdot\frac{7}{4}=5-\frac{7}{6}\)

\(\left(x+\frac{4}{3}\right)\cdot\frac{7}{4}=\frac{23}{6}\)

\(\Rightarrow x+\frac{4}{3}=\frac{23}{6}:\frac{7}{4}=\frac{46}{21}\)

\(\Rightarrow x=\frac{46}{21}-\frac{4}{3}=\frac{6}{7}\)

Ủng hộ mk nka!!!^_^^_^^_^

a) 435 - ( x + 16 ) = 25

x+ 16 = 435 - 25

x + 16 = 410

x = 410 - 16

x = 394

b) (x+4/3 ) * 7/4 = 23/6

x+4/3= 23/6 : 7/4

x+4/3 = 46/21

x = 46/21  - 4/3

x = 6/7

Đáp số : 1

4/7x17/18x7/4x18/17

1/1

1

5,5 + \(\dfrac{3}{4}\) - 5 + \(\dfrac{1}{4}\)

(5,5 - 5) + (\(\dfrac{3}{4}\) + \(\dfrac{1}{4}\))

= 0,5  + 1

= 1,5 

\(\dfrac{5}{2}\) x  \(\dfrac{2}{3}\) + \(\dfrac{1}{4}\) : \(\dfrac{3}{2}\)

= \(\dfrac{5}{2}\) x \(\dfrac{2}{3}\) + \(\dfrac{1}{4}\) x \(\dfrac{2}{3}\)

=  (\(\dfrac{5}{2}\) + \(\dfrac{1}{4}\)) x \(\dfrac{2}{3}\)

= (\(\dfrac{10}{4}\) + \(\dfrac{1}{4}\)) x \(\dfrac{2}{3}\)

= \(\dfrac{11}{4}\) x \(\dfrac{2}{3}\)

= \(\dfrac{11}{6}\) 

Tính \(x\): 

  435  - [\(x\) + 16] = 425 : 17

  435 - [\(x\) + 16] = 25

          [\(x\) + 16] = 435 - 25

           \(x\) + 16 = 410

           \(x\)        = 410 - 16

          \(x\)         = 394

dễ thật nên tui đố mọi người đó

hihihiihihihi

\(2\frac{3}{4}.\frac{1}{2}-\frac{1}{2}.\frac{3}{7}+\frac{1}{3}\)

\(=\frac{11}{4}.\frac{1}{2}-\frac{1}{2}.\frac{3}{7}+\frac{1}{3}\)

\(=\frac{11}{8}-\frac{3}{14}+\frac{1}{3}\)

\(=\frac{251}{168}\)

Bài 1 : a, thực hiện phép tính : 

\(2\frac{3}{4}×\frac{1}{2}-\frac{1}{2}×\frac{3}{7}+\frac{1}{3}\)

\(=\frac{11}{4}×\frac{1}{2}-\frac{1}{2}×\frac{3}{7}+\frac{1}{3}\)

\(=\frac{1}{2}×\left(\frac{11}{4}-\frac{3}{7}\right)+\frac{1}{3}\)

\(=\frac{1}{2}×\frac{65}{28}+\frac{1}{3}\)

\(=\frac{65}{56}+\frac{1}{3}\)

\(=\frac{251}{168}\)

b , Tìm x biết : 

a, 435- ( x + 16 ) = 425 : 17 

435 - ( x + 16 ) = 25 

x + 16 = 435 - 25 

x + 16 = 410 

x  = 410 - 16 

x = 394 

Vậy x = 394 

b, ( x + 3/4 ) × 7/4 = 5 - 7/6 

( x + 3/4 ) × 7/4 = 23/6 

x + 3/4 = 23/6 : 7/4 

x + 3/4 = 23/6 × 4/7 

x + 3/4 = 46/21 

x = 46/21 - 3/4 

x = 121/84

Vậy x = 121/84