The Following Seasonal Indexes and Trend Line Were Computed from Five

question 9

Essay

The following seasonal indexes and trend line were computed from five years of quarterly sales data.
Trend line: ŷ_t = 325 + 18.5t, t = 1, 2, 3, …20. $$\begin{array} { | c c | } \hline \text { Quarter } & \text { Seasonal index } \\\hline 1 & 1.35 \\2 & 1.22 \\3 & 0.88 \\4 & 0.55 \\\hline\end{array}$$ Forecast the sales for the next four quarters.

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Definitions:

Directional Control

The mechanism or system used to steer or change the direction of a vehicle or a machine part.

Pilot

Any of a number of devices that receives a signal and then effects an action; can also be known as a relay.

Spool

A cylindrical device around which materials such as thread, wire, or film are wound for storage.

Swashplate Pump

A type of hydraulic pump where a rotating swashplate controls the flow of fluid, used in various high-pressure hydraulic systems.