Question

Elio makes candles that are 14 cm tall. Each candle burns 8 hours before going out. He is wondering how many hours a 21 cm tall candle can burn for. He assumes that the relationship between the height of a candle and number of hours it burns is proportional. How long can a 21 cm tall candle burn for?

Answer 1

12 hours

Explanation:

Create a proportion where x is how long the 21 cm candle can burn for:

`(14)/(8)` =
`(21)/(x)`

Cross multiply and solve for x:

14x = 168

x = 12

So, the 21 cm tall candle can burn for 12 hours