The answer is 2/3 in lowest terms.
        
             
        
        
        
The end of his round on Saturday was a -5, and the end of his round on Sunday was a 0.
 
        
             
        
        
        
Answer:
h = -t+20
After 8 hours the candle will be 12 inches
Step-by-step explanation:
We have 2 points (time, inches)
  (3,17)  and (5,15)
We can find the slope
m = (y2-y1)/(x2-x1)
    = (15-17)/(5-3)
    = -2/2
    = -1
We can use point slope form
y-y1 = m(x-x1)
Replace y with h and x with t
h-17 = -1 (t-3)
Distribute
h-17 = -t+3
Add 17 to each side
h-17+17 = -t+3+17
h = -t+20
After 8 hours
h = -t+20
h = -8+20
h= 12