“+”=> {$userArray['age']+1}
“-”=> {$userArray['age']-1}
“*”=> {$userArray['age']*2}
“/”=> {$userArray['age']/2}
“%”=> {$userArray['age']%2}
“+”=> {$userObj->age+1}
“-”=> {$userObj->age-1}
“*”=> {$userObj->age*2}
“/”=> {$userObj->age/2}
“%”=> {$userObj->age%2}