Answer:
Greatest number of hours = 3
Explanation:
Given that:
Initial charges = $10
Per hour charges = $5
Number of hours = h
Equation;
t = 10 + 5h
For finding the hours for $25, we will put t=25 in the equation
25 = 10 + 5h
25 - 10 = 5h
5h = 15
Dividing both sides by 5

Hence,
Greatest number of hours = 3