Problema Solution
It took Andrew 40 seconds to burn half a CD. What is Andrew's "burning rate" in CDs per minute?
Answer provided by our tutors
Let
v = "burning rate" in CDs per minute
n = 1/2 CDs the number of CD burnt
t = 40 s = 40/60 min = 2/3 min the time of the burning process
v = n/t
v = (1/2)/(2/3)
v = (1*3)/(2*2)
v = 3/4
v = 0.75 CDs per min
Andrew's "burning rate" is 0.75 CDs per minute.