Even Steven has a bit of a morbid fixation with odds. He wants to know how many odd numbers there are between 3000 and 8000 without any digits repeated? See if you can help old Steve render the count!
As always, try to hide your response so other get a chance to have fun counting too!
The last digit is 3, 5 or 7. There are 3 choices for the ones place, 4 choices for the thousands place, 8 choices for the hundreds place, and 7 choices for the tens place. 4 * 8 * 7 * 3 = 672
The last digit is 1, or 9. There are 2 choices for the ones place, 5 choices for the thousands place, 8 choices for the hundreds place, and 7 choices for the tens place. 5 * 8 * 7 * 2 = 560
Even Steven
29 Apr '21 03:29
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