Question
How many 4-digit whole numbers are there? For example, 1220 is acceptable but 0678 is not.
How do you do permutation and repetition?
How do you do permutation and repetition?
Answers
Anonymous
since first bar cannot be a zero possibiltiies of first numeral is 9, and since repition is allowed, the last 3 slots are allowed to be 10 therefore,
9 x 10 x 10 x 10 (had u forgotten that it said even or odd numbers only, just simply divide by 2) other than that the answer is 9000.
9 x 10 x 10 x 10 (had u forgotten that it said even or odd numbers only, just simply divide by 2) other than that the answer is 9000.