`@` `\text {Ans}`
`\downarrow`
`a)`
\(24 \div a+24=30\)
`=> 24 \div a = 30 - 24`
`=> 24 \div a = 6`
`=> a = 24 \div 6`
`=> a = 4`
Vậy, `a=4`
`b)`
\( 1974 \div 14+a \times 141=423\)
`=> 141 + a \times 141 = 423`
`=> a \times 141 = 423 - 141`
`=> a \times 141 = 282`
`=> a = 282 \div 141`
`=> a = 2`
Vậy, `a=2`
`c)`
\(120-(45-a \times 4)=115\)
`=> 45 - a \times 4 = 120 - 115`
`=> 45 - a \times 4 = 5`
`=> a \times 4 = 45 - 5`
`=> a \times 4 = 40`
`=> a = 40 \div 4`
`=> a = 10`
Vậy, `a=10`
`d)`
\((a \times 4-44) \div 4=44\)
`=> a \times 4 - 44 = 44 \times 4`
`=> a \times 4 - 44 = 176`
`=> a \times 4 = 176 + 44`
`=> a \times 4 = 220`
`=> a = 220 \div 4`
`=> a = 55`
Vậy, `a = 55.`
a) 24:a+24=30
24:a= 30 - 24
24:a=6
a= 24:6
a=4
______
b) 1974:14+ax141=423
141 + a x 141 = 423
141 x (a+1) = 423
a+1 = 423 : 141
a+1=3
a=3-1
a=2
_____
c) 120-(45-ax4)=115
45 - a x 4= 120 - 115
45 - a x 4= 5
a x 4 = 45 - 5
a x 4 = 40
a = 40:4
a=10
______
d) (ax4-44):4=44
a x 4 - 44 = 44 x 4
a x 4 - 44 = 176
a x 4 = 176 + 44
a x 4 = 220
a= 220:4
a=55
a) \(24:a+24=30\)
\(\Rightarrow24:a=30-24\)
\(\Rightarrow24:a=6\)
\(\Rightarrow a=24:6\)
\(\Rightarrow a=4\)
b) \(1974:14+a\cdot141=423\)
\(\Rightarrow141+a\cdot141=423\)
\(\Rightarrow141\cdot\left(1+a\right)=423\)
\(\Rightarrow1+a=423:141\)
\(\Rightarrow1+a=3\)
\(\Rightarrow a=3-1\)
\(\Rightarrow a=2\)
c) \(120-\left(45-a\cdot4\right)=115\)
\(\Rightarrow45-a\cdot4=120-115\)
\(\Rightarrow45-a\cdot4=5\)
\(\Rightarrow a\cdot4=45-5\)
\(\Rightarrow a=40:4\)
\(\Rightarrow a=10\)
d) \(\left(a\cdot4-44\right):4=44\)
\(\Rightarrow a\cdot4-44=44\cdot4\)
\(\Rightarrow a\cdot4-44=176\)
\(\Rightarrow a\cdot4=176+44\)
\(\Rightarrow a\cdot4=220\)
\(\Rightarrow a=220:4\)
\(\Rightarrow a=55\)
