How many 3-digit numbers can be created using the numbers 7, 8, 9, 10?

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Answer 1 · 2018-01-22T22:00:35

See a solution process below:

first, using the number 10, because it is 2 digits, we can only use the 1 of the other digits either before or after the 10.

So this would give us: #3 xx 2 = 6#, 3 digit numbers.

710; 810; 910; 107; 108; 109

Then we can combine the 3 single digit numbers in:

#3 xx 2 xx 1 = 6#, additional 3 digit numbers:

#789; 798; 879; 897; 978; 987

Therefore there are a total of 12 three digit numbers you can create.