400=0.1x

Solution for 400=0.1x equation:

Simplifying
400 = 0.1x

Solving
400 = 0.1x

Solving for variable 'x'.

Move all terms containing x to the left, all other terms to the right.

Add '-0.1x' to each side of the equation.
400 + -0.1x = 0.1x + -0.1x

Combine like terms: 0.1x + -0.1x = 0.0
400 + -0.1x = 0.0

Add '-400' to each side of the equation.
400 + -400 + -0.1x = 0.0 + -400

Combine like terms: 400 + -400 = 0
0 + -0.1x = 0.0 + -400
-0.1x = 0.0 + -400

Combine like terms: 0.0 + -400 = -400
-0.1x = -400

Divide each side by '-0.1'.
x = 4000

Simplifying
x = 4000