Use a $3-$period moving average to forecast demand for July.

$\backslash$table$[[$Month$,$Jan,Feb,Mar,Apr,May,Jun$],[$Demand$,1,050,980,1,200,1,350,1,180,1,250]]$

Calculate a $3-$period weighted moving average with $W_t=0\mathrm{.}5,W_{t-1}=0\mathrm{.}3,W_{t-2}=0\mathrm{.}2$ to forecast demand for July.