Answer: it would take the cyclist 8.5 hours to travel 153 miles.
Step-by-step explanation: We can use proportions to solve this problem.
Let's define:
x = the time it would take for the cyclist to travel 153 miles.
Using proportions, we can set up the following equation:
45 miles / 2.5 hours = 153 miles / x
We can then cross-multiply and solve for x:
45 * x = 2.5 * 153
45x = 382.5
x = 382.5 / 45
x = 8.5