Does the scalar addition obey ordinary addition rules?

Explanation:

In scalar addition we have to do only the sum of magnitude as we know that the scalar quantities don't have direction.

since it is the scalar quantity the direction will be same for all the magnitudes.

the skeletons of most mammals reach a certain size and then stop growing. however, many animals, including some mammals, keep growing throughout their lives. kangaroos, for example, just keep growing and growing until they die. also, the longer an animal lives the greater the chance it might catch some deadly disease.