To find how long $451 will last, given that 2 days and 1 hour costs $539, let's go through the calculations.

1. Convert 2 days and 1 hour to hours:

   • $2$ days $= 2 \times 24 = 48$ hours.
   • Adding the additional 1 hour, we have: $48 + 1 = 49 \text{ hours}$

2. Determine the hourly rate: $\text{Hourly rate} = \frac{539}{49} \approx 11 \text{ dollars per hour}$

3. Calculate the number of hours for $451: $\text{Hours for } 451 = \frac{451}{11} \approx 41 \text{ hours}$

So, $451 will last approximately 41 hours.

Would you like further details on any step?

Here are some additional related questions to explore:

1. What if the rate increased by 10%? How long would $451 last?
2. If only $400 were available, how many hours would it cover?
3. How many hours could $600 cover at the same rate?
4. If there was a fixed additional fee, how would that affect the calculation?
5. How would this calculation change if the rate was per minute rather than per hour?

Tip: Always double-check units (hours, days, etc.) when converting time in rate problems to avoid mistakes.