Solve 10+x/90+(10+x)*100%=20%

$$\frac{ 10+x }{ 90+(10+x) } \times 100 \% =20 \%$$

Solve for x

$$x = \frac{25}{2} = 12\frac{1}{2} = 12.5$$

Steps for Solving Linear Equation

Variable x cannot be equal to -100 since division by zero is not defined. Multiply both sides of the equation by 100\left(x+100\right), the least common multiple of 90+10+x,100.

$$100\left(10+x\right)\times \frac{100}{100}=\left(x+100\right)\times 20$$

Divide 100 by 100 to get 1.

$$100\left(10+x\right)\times 1=\left(x+100\right)\times 20$$

Multiply 100 and 1 to get 100.

$$100\left(10+x\right)=\left(x+100\right)\times 20$$

Use the distributive property to multiply 100 by 10+x.

$$1000+100x=\left(x+100\right)\times 20$$

Use the distributive property to multiply x+100 by 20.

$$1000+100x=20x+2000$$

Subtract 20x from both sides.

$$1000+100x-20x=2000$$

Combine 100x and -20x to get 80x.

$$1000+80x=2000$$

Subtract 1000 from both sides.

$$80x=2000-1000$$

Subtract 1000 from 2000 to get 1000.

$$80x=1000$$

Divide both sides by 80.

$$x=\frac{1000}{80}$$

Reduce the fraction \frac{1000}{80} to lowest terms by extracting and canceling out 40.

$$x=\frac{25}{2}$$