To calculate the number of seconds in 2.5 hours, we proceed as follows:

1. There are 60 minutes in an hour.
2. There are 60 seconds in a minute.
3. Multiply the hours by the number of minutes per hour and then by the number of seconds per minute:

$2.5 \, \text{hours} \times 60 \, \text{minutes/hour} \times 60 \, \text{seconds/minute}$

$2.5 \times 60 \times 60 = 9,000 \, \text{seconds}$

So, there are 9,000 seconds in 2.5 hours.

Would you like more details or have any questions?

Here are 5 related questions:

1. How many seconds are in 1.5 hours?
2. How many hours are there in 3600 seconds?
3. How many minutes are there in 2.5 hours?
4. If a task takes 0.75 hours, how many seconds does it take?
5. Convert 7,200 seconds to hours and minutes.

Tip: For quick conversions, remember that 1 hour equals 3,600 seconds!