Update parent scope variable in AngularJS

Question

I have two controllers, one wrapped within another. Now I know the child scope inherits properties from the parent scope but is there a way to update the parent scope variab

Answer 1

This also works (but not sure whether this follows best practice or not)

app.controller('ctrlParent',function($scope) {
    $scope.simpleValue = 'x';
});

app.controller('ctrlChild',function($scope){
    $scope.$parent.simpleValue = 'y';
});