ANSWER
3.75 hours
EXPLANATION
John spent 12.5 hours at the water park and he estimated that he spent 30% of that time waiting in line.
To find the amount of time he soent waiting in line, we have to simply find 30% of 12.5 hours.
That is:
[tex]\frac{30}{100}\cdot\text{ 12.5 = 3.75 hours}[/tex]It is reasonable to say that he spent 3.75 hours waiting in line.