The cardinality of a set is the number of elements in the set. Let's determine the cardinality for each given set:

1. A = {The first five counting numbers}

   • The first five counting numbers are 1, 2, 3, 4, and 5.
   • A = 5

2. B = {Months of the year that have fewer than 31 days}

   • The months with fewer than 31 days are February, April, June, September, and November.
   • B = 5

3. C = {Present President of the Philippines}

   • There is only one current president.
   • C = 1

4. D = {Consonants in the word MATHEMATICS}

   • The consonants in "MATHEMATICS" are M, T, H, M, T, C, S.
   • D = 7

5. E = {Counting numbers less than 16 and divisible by 3}

   • The numbers less than 16 that are divisible by 3 are 3, 6, 9, 12, and 15.
   • E = 5

Let me know if you'd like more details on any of the answers!

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5 Related Questions:

1. What is the difference between a finite set and an infinite set?
2. How do you find the cardinality of an infinite set?
3. What is the union of two sets and how does it affect cardinality?
4. How can we use set notation to describe more complex sets?
5. What are the properties of subsets in terms of cardinality?

Tip:

When finding the cardinality of a set, always ensure you accurately identify all distinct elements without repetitions.