Construct an Even Number: Divisibility Test with 8, 1, 3, 7

To solve this problem, we'll follow these steps:

• Step 1: Identify and understand the requirement for divisibility by 2.
• Step 2: Determine the potential numbers by rearranging the digits to satisfy the divisibility rule.
• Step 3: Confirm by checking the last digit of the arranged number.

Now, let's work through each step:
Step 1: A number is divisible by 2 if its last digit is even. Among the given digits (8, 1, 3, 7), only 8 is even.
Step 2: Rearrange the digits so that the last digit is 8. Potentially, using all digits, the number 1378 can be formed.
Step 3: Check that 1378 ends with 8, confirming it is divisible by 2.

Therefore, the solution to the problem is 1378.