
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.


\(a,\frac{2}{3}+\frac{1}{2}+\frac{1}{6}=\frac{4}{6}+\frac{3}{6}+\frac{1}{6}=\frac{8}{6}=\frac{4}{3}\)
\(b,\frac{5}{12}+\frac{5}{6}-\frac{3}{4}=\frac{5}{12}+\frac{10}{12}-\frac{9}{12}=\frac{6}{12}=\frac{1}{2}\)
a) 2/3 + 1/2 + 1/6 = 4/6 + 3/6 + 1/6 = 7/6 + 1/6 = 8/6 = 4/3
b) 5/12 + 5/6 - 3/4 = 5/12 + 10/12 - 9/12 = 15/12 - 9/12 = 6/12 = 1/2
c) 1/3 x 3/5 x 2/5 = 3/15 x 2/5 = 6/75 = 2/25
d) 15/16 : 3/8 x 3/4 = 15/16 x 8/3 x 3/4 = 1/10 x 3/4 = 3/40

a, \(\frac{4}{7}x\frac{5}{7}+\frac{3}{7}x\frac{5}{6}\)
= ( \(\frac{4}{7}+\frac{3}{7}\)) x \(\frac{5}{7}x\frac{5}{6}\)
= 1 x \(\frac{5}{7}x\frac{5}{6}\)
= \(\frac{5}{7}x\frac{5}{6}\)
= \(\frac{25}{42}\)
Tương tự mấy câu sau cũng làm như thế này

A) 1000000 - 107492 : 154 x 28 + 1000
= 1000000 - 19544 + 1000
= 981456
B) 8/15 + 4/7 + 14/30 + 12/21 + 5
= 15/7 + 5
= 50/7
C) 9/13 : 6/11 - 5/12 : 6/11
= 9/13 x 11/6 - 5/12 x 11/6
= (9/13 - 5/12) x 11/6
= 43/156 x 11/6
= 473/936
Bài 2
1) X x2 + X x 1/5 = 8/5
X x (2 + 1/5 ) = 8/5
X x 11/5 = 8/5
X = 8/5 x 5/11
X = 8/11
2) X : 3/8 = 4/3 : 3/6
X : 3/8 = 8/3
X = 8/3 x 3/8
X = 1
a) 1 000 000 - 107 492 : 154 x 28 + 1000
= 1 000 000 - 698 x 28 + 1000
= 1 000 000 - 19544 + 1000
= 980 456 + 1000
= 981 456
b) 8/15 + 4/7 + 14/30 + 12/21 + 5
= ( 8/15 + 14/30 ) + ( 4/7 + 12/21 ) + 5
= ( 16/30 + 14/30 ) + ( 12/21 + 12/21 ) + 5
= 30/30 + 24/21 + 5
= 1 + 24/21 + 5
= ( 1 + 5 ) + 24/21
= 6 + 24/21
= 150/21
= 50/7

a, \(x:3\dfrac{5}{6}=2\dfrac{8}{15}\)
\(x:\dfrac{23}{6}\) = \(\dfrac{38}{15}\)
\(x=\dfrac{38}{15}\times\dfrac{23}{6}\)
\(x=\dfrac{437}{45}\)
b, \(\dfrac{12}{15}:x+\dfrac{4}{3}=3\dfrac{2}{3}\)
\(\dfrac{12}{15}:x+\dfrac{4}{3}=\dfrac{11}{3}\)
\(\dfrac{12}{15}:x=\dfrac{11}{3}-\dfrac{4}{3}\)
\(\dfrac{12}{15}:x=\dfrac{7}{3}\)
x= \(\dfrac{12}{15}:\dfrac{7}{3}=\dfrac{12}{35}\)
\(c)x:\dfrac{5}{4}=\dfrac{9}{5}+\dfrac{1}{2}\)
\(x:\dfrac{5}{4}=\dfrac{23}{10}\)
\(x=\dfrac{23}{10}\times\dfrac{5}{4}\)
\(x=\dfrac{23}{8}\)

1. a
\(\dfrac{8}{5}-\dfrac{5}{6}\cdot\dfrac{3}{4}\)
\(=\dfrac{8}{5}-\dfrac{5\cdot3}{3\cdot2\cdot4}\)
\(=\dfrac{8}{5}-\dfrac{5}{8}=\dfrac{39}{40}\)
1.b
\(=\dfrac{7}{8}+\dfrac{5}{6}\cdot\dfrac{3}{2}\)
\(=\dfrac{7}{8}+\dfrac{5\cdot3}{3\cdot2\cdot2}\)
\(=\dfrac{7}{8}+\dfrac{5}{4}=\dfrac{17}{8}\)
2.a
\(\dfrac{4}{5}+x=\dfrac{11}{10}\)
\(x=\dfrac{11}{10}-\dfrac{4}{5}=\dfrac{3}{10}\)
2.b
\(x-\dfrac{3}{4}=\dfrac{5}{7}\)
\(x=\dfrac{5}{7}+\dfrac{3}{4}=\dfrac{41}{28}\)

a)\(\frac{2}{3}\cdot x+\frac{1}{4}=\frac{5}{6}\)
\(\frac{2}{3}\cdot x=\frac{5}{6}-\frac{1}{4}=\frac{7}{12}\)
\(x=\frac{7}{12}:\frac{2}{3}=\frac{7}{8}\)
b) \(\frac{7}{12}-\frac{5}{6}\cdot x=\frac{1}{4}:\frac{2}{3}\)
\(\frac{7}{12}-\frac{5}{6}\cdot x=\frac{3}{8}\)
\(\frac{5}{6}\cdot x=\frac{7}{12}-\frac{3}{8}=\frac{5}{24}\)
\(x=\frac{5}{24}:\frac{5}{6}=\frac{1}{4}\)
c) \(2\frac{1}{3}-\left(x+1\right)=\frac{5}{9}\)
\(\frac{7}{3}-\left(x+1\right)=\frac{5}{9}\)
\(x+1=\frac{7}{3}-\frac{5}{9}=\frac{16}{9}\)
\(x=\frac{16}{9}-1=\frac{7}{9}\)
d) \(\frac{2\cdot x+1}{15}=\frac{3}{5}\)
\(\left(2\cdot x+1\right):15=\frac{3}{5}\)
\(2\cdot x+1=\frac{3}{5}\cdot15=9\)
\(2\cdot x=9-1=8\)
\(x=8:2=4\)
a, 2/3 . x +1/4=5/6
2/3 . x=5/6-1/4
2/3 . x=10/12 -3/12
2/3 . x=7/12
x= 7/12 : 2/3
x=7/8
Vậy x=7/8

a) x + 1/15 = 1/3 - 1/4 = 4/12 - 3/12 = 1/12.
=> x = 1/12 - 1/15 = 5/60 - 4/60 = 1/60.
b) x - 5/12 = 1/3 + 1/4 = 4/12 + 3/12 = 7/12.
=> x = 7/12 + 5/12 = 1
c) x x 2/7 = 3/4 x 4/15 = 1/5
=> x = 1/5 : 2/7 = 1/5 x 7/2 = 7/10
d) x : 3/8 = 4/3 : 3/6 = 4/3 x 2 = 8/3
=> x = 8/3 x 3/8 = 1

Bài 1
\(a,\)6 giờ 45 phút : 5 = 1 giờ 21 phút
\(b,\)12 giờ 36 phút : 12 = 1 giờ 3 phút
\(c,\)17,64 - ( 5 - 6,36 ) = 19
\(d,\)53,68 x 15,6 - 53,68 x 5,6 = 53,68( 15,6 - 5,6 ) = 536 , 8
Bài 2 :
\(b,\)\(x\times0,1=\frac{2}{5}\)
\(\Rightarrow x=\frac{2}{5}\div0,1\)
\(\Rightarrow x=4\)

a) (x + 1/3) : 4/5 = 5/2
x+1/3=5/2*4/5
x+1/3=2
x=2-1/3
x=5/3
b) ( x - 1/3) * 1/2 = 1/3
x-1/3=1/3:1/2
x-1/3=2/3
x=2/3+1/3
x=1
c) 12*1/2 + 15*3/6 < x < 4*2/5 * 1/2
27/2<x<4/5
vì 27/2>4/5 nên đề sai
d) 575 - (6x * 70) = 445
6x*70=575-445
6x*70=130
6x=130:70
6x=13/7
x=13/7:6
x=13/42
e) 8,75 * x + 3,75 * x + 28,7(thiếu dữ kiện)
f) 3/4 * x = 1/4 + 0,75
3/4*x=1
x=1:3/4
x=4/3
**** nhé
a) (x + 1/3) : 4/5 = 5/2
x + 1/3 = 5/2 . 4/5
x + 1/3 = 2
x = 2 - 1/3
x = 5/3
\(x-\frac{1}{6}=\frac{5}{12}\)
\(x=\frac{5}{12}+\frac{1}{6}\)
\(x=\frac{5}{12}+\frac{2}{12}\)
\(x=\frac{7}{12}\)
\(x+\frac{3}{4}=\frac{5}{3}\)
\(x=\frac{5}{3}-\frac{3}{4}\)
\(x=\frac{20}{12}-\frac{9}{12}\)
\(x=\frac{11}{12}\)