Question

A combination lock requires three numbers from 1 to 25. how many combinations are possible? did you use the sum rule or the product rule? (note that although we use the term combination with locks, order matters.)

Answer 1

Combinations possible = 25 * 25 * 25. Product rule

The point is that numbers can be reused. 1 5 1 is a valid combination as is   4 4 4 

20 * 5 * 1 is a valid combination as is 1 25 5

So the answer is 15625 "combinations" are possible <<<<< answer