Many people find it difficult to see which of two large numbers is greater, unless they are reading on paper and take up a pencil and count the groups of three.

Many people find it difficult to see which of two large numbers is greater, unless they are reading on paper and take up a pencil and count the groups of three. This issue must come up a lot in simple-English. The solution is to introduce scientific notation, and to have a link to that. (As has been pointed out, mass is a tricky word, being used here.) Perhaps another method would be to invent something quirky, saying perhaps "4+(20 digits)" or something. In this particular case, there is another solution: do not quote the individual numbers, but only their ratio. Anyone can tell that "1000" is big and "1/1000" is small, because all that's needed is to see if there are more than two or so digits.