\(a,x:0,4=3,67\\ x=3,67\times0,4\\ x=1,468\\ b,x-34,4=252,7\\ x=252,7+34,4=287,1\\ c,75,8:x=10\\ x=75,8:10=7,58\\ d,651,6-x=280,8\\ x=651,6-280,8=370,8\)

a)x|0,4=3,67

x=3,67x0,4

x=1,468

b)x-23,4=28,6

x=28,6-23,4

x=5,2

\(51,3:x+23,4:x=9\)

\(\left(51,3+23,4\right):x=9\)

\(74,7:x=9\)

\(x=8,3\)

\(\frac{\left(23,4+15,5\right)\cdot7+\left(23,4+19,5\right)\cdot3+11}{0,55\cdot2\cdot30+5\cdot11+2,75\cdot8}\)

\(=\frac{\left(23,4+15,5\right)\cdot\left(7+3\right)+12+11}{1,1\cdot30+5\cdot11+11\cdot2}\)

\(=\frac{38,9\cdot10+23}{11\cdot\left(3+5+2\right)}=\frac{412}{110}=\frac{206}{55}\)

Chúc em học tốt!

(Mong em đừng đăng câu hỏi linh tinh lên nữa)
 

a: \(12:\dfrac{3}{4}+75\%\cdot\dfrac{1}{2}-16\cdot50\%\)

\(=12\cdot\dfrac{4}{3}+\dfrac{3}{4}\cdot\dfrac{1}{2}-16\cdot0,5\)

\(=16-8+\dfrac{3}{8}\)

\(=8,375\)

b: \(75\%\cdot4+22,5:3-1\dfrac{3}{5}\)

\(=0,75\cdot4+7,5-1,6\)

\(=3+7,5-1,6\)

=10,5-1,6

=8,9

X – 23,4 = 8,4 x 2 
X – 23,4 = 16,8   

X    = 23,4 + 16,8

X    = 40,2

a.23,4 x 9+23,4

=23,4 x 9+23,4 x 1

=23,4 x (9+1)

=23,4 x 10

=234

b.15,3 x 11-15,3

=15,3 x 11-15,3 x 1

=15,3 x (11-1)

=15,3 x 10

=153

tick cho mình nha

a, = 234

b, = 153

X – 23,4 = 8,4 x 2 
X – 23,4 = 16,8

X = 23,4 + 16,8

X = 40,2

X – 23,4 = 8,4 x 2

X – 23,4 = 8,4 x 2 
X – 23,4 = 16,8

X = 23,4 + 16,8

X = 40,2