x = 23/69 - 17/153

a)\(\Leftrightarrow\)\(x=\dfrac{2323}{4646}-\dfrac{1313}{2828}\)

\(\Leftrightarrow\)\(x=\dfrac{1}{28}\)

b)\(\Leftrightarrow\)\(x=\dfrac{23}{69}-\dfrac{17}{153}\)

\(\Leftrightarrow\)\(x=\dfrac{2}{9}\)

a) \(\dfrac{1313}{2828}\) + \(x\) = \(\dfrac{2323}{4646}\)

\(\dfrac{13}{28}\) + \(x\) = \(\dfrac{1}{2}\)

\(x=\dfrac{1}{2}-\dfrac{13}{28}\)

\(x=\dfrac{14}{28}-\dfrac{13}{28}\)

\(x=\dfrac{1}{28}\)

\(\frac{1313}{2828}+x=\frac{2323}{4646}\)

hay \(\frac{13}{28}+x=\frac{1}{2}\)

\(x=\frac{1}{2}-\frac{13}{28}\)

\(x=\frac{1}{28}\)

\(\frac{23}{69}-x=\frac{17}{153}\)

hay \(\frac{1}{3}-x=\frac{1}{9}\)

\(x=\frac{1}{3}-\frac{1}{9}\)

\(x=\frac{2}{9}\)

\(a,\frac{1313}{2828}+x=\frac{2323}{4646}\)

\(\frac{13}{28}+x=\frac{1}{2}\)

\(x=\frac{1}{2}-\frac{13}{28}=\frac{1}{28}\)

\(b,\frac{5}{7}+\frac{x}{35}=\frac{4}{5}\)

\(\frac{x}{35}=\frac{4}{5}-\frac{5}{7}=\frac{3}{35}\)

\(\Rightarrow x=3\)

\(c,\frac{23}{69}-x=\frac{17}{153}\)

\(\frac{1}{3}-x=\frac{1}{9}\)

\(x=\frac{1}{3}-\frac{1}{9}=\frac{2}{9}\)

\(a,\frac{1313}{2828}+x=\frac{2323}{4646}\)

\(\frac{13}{28}+x=\frac{1}{2}\)

\(x=\frac{1}{2}-\frac{13}{28}=\frac{1}{28}\)

\(b,\frac{5}{7}+\frac{x}{35}=\frac{4}{5}\)

\(\frac{x}{35}=\frac{4}{5}-\frac{5}{7}=\frac{3}{35}\)

\(\Rightarrow x=3\)

\(c,\frac{23}{69}-x=\frac{17}{153}\)

\(x=\frac{23}{69}-\frac{17}{153}=\frac{2}{9}\)

a: =>x+7/4=6:2/3=9

=>x=29/4

b: =>x:5/3=7/5

=>x=7/5*5/3=7/3

c:=>x+1/6=5/3

=>x=10/6-1/6=3/2

d: =>x+4/5=4/5+3/7+3/5

=>x=3/7+3/5=36/35

e: =>x/35=4/5-5/7=3/35

=>x=3

f: =>13/28+x=1/2

=>x=1/28

g: =>1/3-x=1/9

=>x=2/9

đề sai rồi x đâu

Tìm x nhưng ko có x

a/ số các số hạng:

  ( 999-1) :1+1 = 999 (số)

tổng :

( 999 + 1 ) x 999 : 2 = 499500

b/số các số hạng:

( 1001 - 21 ) : 2 + 1 = 491(số)

tổng :

( 1001 + 21 ) x 491 : 2 = 250901

c/số các số hạng:

( 128 - 23 ) : 1 + 1 =105(số)

tổng :

( 128 + 23 ) x 105 : 2 = 128

d/số các số hạng:

( 155 - 15 ) : 2 + 1 = 71(số)

tổng :

( 155 + 15 ) x 71 : 2 =6035

Hướng dẫn giải:

a) 987 x 23 + 987 x 77

= 987 x (23 + 77)

= 987 x 100

= 98700

b) 2928 x 69 – 1928 x 69

= (2928 – 1928) x 69

= 1000 x 69

= 69000