In a survey of 500 residents in a certain town, 274 said they were opposed to constructing a new shopping mall. Compute the P-value for testing H subscript 0 : p less or equal than 0.5 versus H subscript 1 : p greater than 0.5, where p denotes the proportion of town residents who are opposed to the new shopping mall. Round your answer to four decimal places.

The GCF of 48 and 72 is 24.
Here is how to find it.
First do the prime factorization of each number:
48 = 6 x 8 = 2 x 3 x 2 x 4 = 2 x 3 x 2 x 2 x 2  or 2⁴ x 3
72 = 8 x 9 = 2 x 2 x 2 x 3 x 3 or 2³ x 3²
When we find the Greatest Common Factor we only use what they have in common and to the least power  (isn't that interesting)
So  we have 2³ and 2⁴  but we have to use the least power which is 2³
We have 3 (in 48) and 3² (in 72) but we can only use 3 (the least power  3=3¹) 
Multiply those two numbers  2³ x 3 and you get 8 x 3 which is 24 and is the GCF.