16=r(400)

Solution for 16=r(400) equation:

Simplifying
16 = r(400)

Reorder the terms for easier multiplication:
16 = 400r

Solving
16 = 400r

Solving for variable 'r'.

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

Add '-400r' to each side of the equation.
16 + -400r = 400r + -400r

Combine like terms: 400r + -400r = 0
16 + -400r = 0

Add '-16' to each side of the equation.
16 + -16 + -400r = 0 + -16

Combine like terms: 16 + -16 = 0
0 + -400r = 0 + -16
-400r = 0 + -16

Combine like terms: 0 + -16 = -16
-400r = -16

Divide each side by '-400'.
r = 0.04

Simplifying
r = 0.04