Problem #$1$

Here are the data for the past $21$ months for actual sales of a particular product:

Develop a forecast for the Month of October using

a$)4-$months moving average

b$)12-$months moving average

c$)3-$months weighted moving average. Weight the most recent month $\mathrm{.}5,$ the second most recent $\mathrm{.}25,$ and the third $\mathrm{.}25$

d$)$ Exponential smoothing and assuming alpha of $\mathrm{.}3$ and forecast for September this year of $375.$

e$)$ Exponential smoothing with trend using same assumptions as in part D plus delta of $\mathrm{.}2$ and September this year trend forecast of $30.$

f$)$ Linear regression

If the actual sales in October were $440,$ which model is the most accurate in predicting October$$s demand?