To express the remaining length of a candle $L$ (in inches) in terms of the number of hours $t$ that have elapsed since the candle was lit, you need to know two key pieces of information:

1. The initial length of the candle, denoted by $L_0$ (in inches).
2. The rate at which the candle burns, denoted by $r$ (in inches per hour).

Assuming the candle burns at a constant rate, the remaining length of the candle $L$ after $t$ hours can be expressed by the following formula:

$L = L_0 - r \cdot t$

Where:

• $L_0$: Initial length of the candle (in inches),
• $r$: Burning rate of the candle (in inches per hour),
• $t$: Time elapsed since the candle was lit (in hours),
• $L$: Remaining length of the candle (in inches).

Example:

If the initial length of the candle is 10 inches and it burns at a rate of 1 inch per hour, after 3 hours the remaining length will be:

$L = 10 - 1 \cdot 3 = 7 \text{ inches}$

Would you like a detailed explanation of this process or have any specific questions about it?

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Here are 5 related questions:

1. How do we calculate the total time it takes for a candle to completely burn out?
2. What happens to the length $L$ if the burning rate is not constant?
3. How would you express the formula if the burning rate changes over time?
4. Can this formula be applied to other materials burning at different rates?
5. How can we determine the burning rate if only the initial and final lengths are known?

Tip: Always check the units of the rate and the time to ensure they are consistent when applying formulas!