The number -5 is all exept for

Restrictions on f(x) = 1/x+5 and g(x) = x-2

Your friend swims on the school team. in his first four races, his times are 24.7, 23.5, 25.6, and 27.2 seconds. which time listed for his next race would make the range larger?

Which one ? is the answer and how to find this answer