Historical demand for a product is as follows:
DEMAND
April 60
May 55
June 75
July 60
August 80
September 75
a. Using a simple four-month moving average, calculate a forecast for October.
b. Using single exponential smoothing with α = 0.2 and a September forecast = 65, calculate a forecast for October.
c. Using simple linear regression, calculate the trend line for the historical data. Say the X axis is April = 1, May = 2, and so on, while the Y axis is demand.
d. Calculate a forecast for October.