Question

Which of the following is a finite set?

• A. $\{x : x \text{ is a natural number}\}$
• B. $\{x : x \text{ is a day of the week}\}$
• C. $\{x : x \text{ is an even integer}\}$
• D. $\{x : x \text{ is a whole number}\}$

Hint:

If you can list all elements completely and the list ends, the set is finite.

Answer 1

The Correct Option is B

Concept:
• Finite set: A set with a limited number of elements.
• Infinite set: A set with endless elements.

Step 1: Check Option (1).
Natural numbers: \[ 1,2,3,4,\ldots \] This is infinite.

Step 2: Check Option (2).
Days of the week: \[ \{\text{Mon, Tue, Wed, Thu, Fri, Sat, Sun}\} \] Total = 7 elements → finite set.

Step 3: Check Option (3).
Even integers: \[ \ldots,-4,-2,0,2,4,\ldots \] Infinite set.

Step 4: Check Option (4).
Whole numbers: \[ 0,1,2,3,\ldots \] Infinite set. Conclusion: Only option (2) is finite. \[ \boxed{\text{Days of the week}} \]