OpenStax, Contemporary Mathematics §1.4 Set Operations with Two Sets · Example 7 · Combinatorics · Sets & logic

Set Operations with Two Sets · Example 7

The number of elements in set $A$ is 10, the number of elements in set $B$ is 20, and the number of elements in $A$ intersection $B$ is 4. Find the number of elements in $A$ union $B$ .

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OpenStax, Contemporary Mathematics · §1.4 Set Operations with Two Sets · Example 7

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