Solve [10+(n-1)*10]10/2=125

$$\frac { [ 10 + ( n - 1 ) \times 10 ] 10 } { 2 } = 125$$

Solve for n

$$n = \frac{5}{2} = 2\frac{1}{2} = 2.5$$

Steps for Solving Linear Equation

Multiply both sides by 2.

$$\left(10+\left(n-1\right)\times 10\right)\times 10=125\times 2$$

Use the distributive property to multiply n-1 by 10.

$$\left(10+10n-10\right)\times 10=125\times 2$$

Subtract 10 from 10 to get 0.

$$10n\times 10=125\times 2$$

Multiply 10 and 10 to get 100.

$$100n=125\times 2$$

Multiply 125 and 2 to get 250.

$$100n=250$$

Divide both sides by 100.

$$n=\frac{250}{100}$$

Reduce the fraction \frac{250}{100} to lowest terms by extracting and canceling out 50.

$$n=\frac{5}{2}$$