A survey of 40 houses revealed that 26 receive the Graphic newspaper and 24 receive the Times newspaper. How many houses receive both newspapers?

Here are the solutions to the problems.

:
Let $G$ be the set of houses receiving Graphic and $T$ be the set of houses receiving Times.
Total houses, $n(G \cup T) = 40$.
Number of Graphic copies, $n(G) = 26$.
Number of Times copies, $n(T) = 24$.

Step 1: Use the Principle of Inclusion-Exclusion to find the number of houses receiving both newspapers.
The formula is $n(G \cup T) = n(G) + n(T) - n(G \cap T)$.
Substitute the given values:

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