Math
posted by Adam .
Suppose that the height (in centimeters) of a candle is a linear function of the amount of time (in hours) it has been burning. After 11 hours of burning, a candle has a height of 18.6 centimeters. After 27 hours of burning, its height is 12.2 centimeters. What is the height of the candle after 15 hours?

Calculate how much height it loses per hour. Call it m.
m = (18.6  12.2)/16 = ___ cm/h
Then solve
(candle height) y = 12.2
= 18.6  m(t  11)
using t = 15
It's called interpolation. 
thanks for the help

Suppose that the height (in centimeters) of a candle is a linear function of the amount of time (in hours) it has been burning. After 10 hours of burning, a candle has a height of 24 centimeters. After 27 hours of burning, its height is 20.6 centimeters. What is the height of the candle after 21 hours?

i don't know the answer at all tall my now