Creating columns of random numbers within a range that do not add to over a set value

#1

I have 5 columns of randomly generated percentages, but need to ensure that the numbers do not add to more than 100% across each row.

Please help!

#2

I’m assuming that each field is a number?
Since there are 5 columns, give each a range from 0 to 20, the total will be 100 or less.