H/16 = 15/3
Cross multiply:
H * 3 = 15 * 16
Simplifying
H * 3 = 15 * 16
Reorder the terms for easier multiplication:
3H = 15 * 16
Multiply 15 * 16
3H = 240
Solving
3H = 240
Solving for variable 'H'.
Move all terms containing H to the left, all other terms to the right.
Divide each side by '3'.
H = 80
Simplifying
H = 80
