SOLUTION: Using all the prime numbers less than 10 how many four-digit even numbers can be made if repetition is not allowed?

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Question 942561: Using all the prime numbers less than 10 how many four-digit even numbers can be made if repetition is not allowed?
Answer by Edwin McCravy(20054) About Me  (Show Source):
You can put this solution on YOUR website!
The prime numbers less than 10 are 2,3,5, and 7.

The 4th digit is the most restrictive.  It can only be 2
since the 4 digit number must be even.

Choose the 4th digit 1 way, as 2.
Choose the 1st digit 3 ways, as 3,5, or 7
Choose the 2nd digit 2 ways.
Choose the 3rd digit 1 way.

Answer: 1×3×2×1 = 6 ways.

They are

3572, 3752, 5372, 5732, 7352, 7532.

Edwin