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Identify odd-even alternation informally

Whole numbers in the familiar counting range can be classified as odd or even: even numbers can be arranged into pairs with none left over, while odd numbers have one left over. In the counting sequence, odd and even numbers alternate, allowing the next type to be predicted and helping distinguish “every other number” from consecutive numbers; formal parity notation, large-number generalizations, and algebraic proofs are not included.

Detailed Explanation: Identify odd-even alternation informally

Numbers take turns being even and odd as we count:

  • Even numbers can be put into pairs with none left over: 2,4,6,82, 4, 6, 8.
  • Odd numbers have one left over after making pairs: 1,3,5,71, 3, 5, 7.

Example

What comes next?

4, 5, 6, 7,  ?4,\ 5,\ 6,\ 7,\ \boxed{\ ?}

Step 1: Name each number.

  • 44 is even.
  • 55 is odd.
  • 66 is even.
  • 77 is odd.

Step 2: Notice the pattern.

The numbers alternate:

even, odd, even, odd\text{even},\ \text{odd},\ \text{even},\ \text{odd}

Step 3: Predict the next type.

After odd comes even.

Step 4: Find the next number.

The number after 77 is 88, and 88 is even.

8\boxed{8}

So, the next number is even.

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