Alock on a fence door has a 4 digit combination. each digit can be any number
between 0 – 9. the only restriction is that all 4 characters cannot be the same
(e. g. , , , how many combinations are possible?
504
512
1
9990

9990

Step-by-step explanation:

Each number combination is 0 to 9. For each combination, it is 10^X. In your problem there are 4 digits. That means it is it is 10^4 = 10000, but because there is a stipulation that the numbers cannot be identical then we have to remove it from the possible combinations. So there are 10 possible identical number combinations. 10000 - 10 = 9990

answer: about 22.67

step-by-step explanation:

answer:

step-by-step explanation: