Question

400,000,000 + 319,238,105

Answer 1

If you like up the numbers vertically it makes it easier to answer the problem:

400,000,000
319,238,105
——————-
719,238,105


And because it is really just zeros it is a fairly simple problem :)

Answer 2

400,000,000 * 319,238,105 + 719,238,105