Problem $13-4($Algo$)$ Coefficient of variation $[$L$013-1]$

Shack Homebuilders Limited is evaluating a new promotional campaign that could increase home sales. Possible outcomes and probabilities of the outcomes are shown next.

$\backslash$table$[[,$Additional Sales in$,],[$Possible Outcomes,Units,Probabilities$],[$Ineffective campaign,$60,0\mathrm{.}20],[$Normal response,$80,0\mathrm{.}20],[$Extremely effective,$120,0\mathrm{.}60]]$

Compute the coefficient of variation.

Note: Do not round intermediate calculations. Round your answer to $3$ decimal places.

Coefficient of variation