Counting Math Example 2
Follow the full solution, then compare it with the other examples linked below.
Example 2
mediumHow many letters are in the word MATHEMATICS? Count carefully — some letters repeat.
Solution
- 1 Write out each letter with a number: M-1, A-2, T-3, H-4, E-5, M-6, A-7, T-8, I-9, C-10, S-11.
- 2 Each letter gets exactly one count, even if it appeared before.
- 3 The last number assigned is 11, so there are 11 letters.
Answer
Counting requires one-to-one correspondence: each object is counted exactly once. Repeating letters are still separate objects in the sequence and must each be assigned their own number.
About Counting
Determining the total number of objects in a set by assigning exactly one number to each object in sequence, where the last number spoken equals the total count (the cardinality of the set).
Learn more about Counting →More Counting Examples
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A student counts the dots on a domino. The left side has 3 dots and the right side has 4 dots. How m
Example 3 easySkip-count by 5s starting at 5 and list the first six multiples.
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