The most important thing in this problem is understanding and then dividing the given units properly. The first thing that is given is that the CD makes 58 1/2 revolutions in 3/4 minutes. We have to first simplify the number of revolutions made by the CD. This will make the problem in hand very easy. Number of revolutions made by the CD = 58 1/2 = 117/2 Then The unit rate = (117/2)/(3/4) = (117 * 4)/(2 * 3) = (117 * 2)/3 = 39 * 2 78 So the unit rate is 78 revolutions per minute.
