Answer:
7 in
Explanation:
Step one:
Given data
A candle that is 10 inches tall burns at a rate of 1/4 inches per hour
let the number of hours take to burn completely be x
and the lenght after certain time be y
So
The expression for the situation is
y= 10-1/4x
y= 10-0.25x
for x= 12
y=10-0.25*12
y=10-3
y= 7 in
After 12 hours the length is 7 in