320=l(1-0.2)

Solution for 320=l(1-0.2) equation:

Simplifying
320 = l(1 + -0.2)

Combine like terms: 1 + -0.2 = 0.8
320 = l(0.8)

Reorder the terms for easier multiplication:
320 = 0.8l

Solving
320 = 0.8l

Solving for variable 'l'.

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

Add '-0.8l' to each side of the equation.
320 + -0.8l = 0.8l + -0.8l

Combine like terms: 0.8l + -0.8l = 0.0
320 + -0.8l = 0.0

Add '-320' to each side of the equation.
320 + -320 + -0.8l = 0.0 + -320

Combine like terms: 320 + -320 = 0
0 + -0.8l = 0.0 + -320
-0.8l = 0.0 + -320

Combine like terms: 0.0 + -320 = -320
-0.8l = -320

Divide each side by '-0.8'.
l = 400

Simplifying
l = 400