Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
chỉ cho biết mẫu số nên ta quy đồng mẫu số
4/7 < x/10 < 5/7 vậy
4/7 = 40/70
x/10 = x/70
5/7 = 50/70
vậy x là
41;42;43;44;45;46;47;48;49
\(\dfrac{4}{7}< \dfrac{x}{10}< \dfrac{5}{7}\)
\(\Rightarrow\dfrac{4.10}{7.10}< \dfrac{7.x}{10.7}< \dfrac{5.10}{7.10}\)
\(\Rightarrow\dfrac{40}{70}< \dfrac{7.x}{70}< \dfrac{50}{70}\)
\(\Rightarrow7.x\in\left\{41;42;43;...49\right\}\)
\(\Rightarrow7.x\in\left\{42;49\right\}\) \(\left(x\in N\Rightarrow7.x⋮7\right)\)
\(7.x=42\Leftrightarrow x=6\)
\(7.x=49\Leftrightarrow x=7\)
\(\frac{x}{27}=\frac{2}{3}\)
Ta có:
\(\frac{2}{3}=\frac{18}{27}\)
\(\Leftrightarrow\frac{x}{27}=\frac{18}{27}\)
\(\Leftrightarrow x=18\)
\(\frac{35}{49}=\frac{10}{y}\)
Ta có:
\(\frac{35}{49}=\frac{5}{7}=\frac{10}{14}\)
\(\Leftrightarrow\frac{10}{14}=\frac{10}{y}\)
\(\Leftrightarrow y=14\)
a: =>x-5/14=6/14-1/14=5/14
=>x=10/14=5/7
b; =>2/9:x=3/6+4/6=7/6
=>x=2/9:7/6=2/9*6/7=4/21
c: =>32:x=8
=>x=4
`@` `\text {Answer}`
`\downarrow`
`a,`
`x - 5/14 = 3/7 - 1/14`
`x - 5/14 = 5/14`
`=> x = 5/14 + 5/14`
`=> x = 5/7`
Vậy, `x = 5/7`
`b,`
`2/9 \div x = 1/2 + 2/3`
`2/9 \div x = 7/6`
`x = 2/9 \div 7/6`
`x = 4/21`
Vậy, `x = 4/21`
`c,`
\(\dfrac{6}{32\div x}=\dfrac{12}{16}\)
`6/(32 \div x) = 3/4`
`32 \div x = 6 \div 3/4`
`32 \div x = 8`
` x = 32 \div 8`
`x = 4`
Vậy, `x = 4`
\(x< 7+\dfrac{1}{7}\\ \Rightarrow x< \dfrac{50}{7}\\ \Rightarrow x=0,1,2,3,4,5,6,7\)
\(7+\dfrac{1}{7}=\dfrac{7.7+1}{7}=\dfrac{50}{7}\simeq7,14\)
\(\Rightarrow X=7;6;5;4;3;2;1;0\)