Problem $10-2($LO $10-3)$ The number of daily calls...

The number of daily calls for the repair of Speedy copy machines has been recorded as follows.

October Calls

$192$

$2127$

$3106$

$4165$

$5125$

$6111$

$7178$

$897$

$($Round all answers to $1$ decimal place.$)$

a$.$ Prepare three$-$period moving$-$average forecasts for the data. What is the error on each day?

b$.$ Prepare three$-$period weighted$-$moving$-$average forecasts using weights of W$1=0\mathrm{.}5,$ W$2=0\mathrm{.}3,$ W$3=0\mathrm{.}2.$ What is the error on each day?

c$.$ Calculate the arithmetic sum of errors and the absolute deviation for both methods.

Which of the two forecasts is better?