# A candle is 7 in tall after burning for 1 h. The same candle is 5.5 in tall after burning for 4 h. How tall will the candle be after burning for 6 h?

##### 2 Answers

The length of the candle (

#### Explanation:

graph{x = (15 - y)/2 [-1, 10, -4.56, 16]}

We know that the length of the candle changed from 7 inches to 5.5 inches between time 1 hour and 4 hours. The rate of change can be calculated in inches per hour.

The height at time 0 can be calculated by plugging in the slope

We know

Plugging both of those values into the equation and using the variables

And we can calculate that at time

Here's a video of a candle burning over a couple of hours to inspire you:

Here's a video

After 6 hours the height will be 4.5 inches

#### Explanation:

The time to reduce to the 7 inches tall is of importance. Unfortunately we do not have the starting height.

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This will have the same ratio as our previously calculated burning rate giving:

Matching denominators: to change 3 to 5 we multiply by

So if we multiply the denominator by

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