We are still cooking the magic in the way!
Problem
Multiplying by 15 requires multiple steps with traditional methods.
Solution
Multiply by 10, then add half of that result.
Benefit
Reduces complex multiplication to simple addition.
Example
24 × 15:
24 × 10 = 240
240 ÷ 2 = 120
240 + 120 = 360
36 × 15:
36 × 10 = 360
360 ÷ 2 = 180
360 + 180 = 540