Choose a Random Cell, Calculate Formula & Round

The title may be a bit deceiving. The setup is:

A1 - Enter any number
A2 - 30% of A1
A3 - 30% of A1
A4 - 25% of A1
A5 - 15% of A1

What I need to get in each cell is a whole number, and when the 4 cells (A2:A5) are added, it totals the amount in A1. Some numbers, like 16, work with a simple =Round($A$1$*.3,0) in Cell B1, but numbers like 8 will return a total value of 7 after rounding and calculating.

Is there a way to make it round a random cell each time so that the sum of A2:A5 always equals the amount entered into A1?

I probably made it more complicated than it has to be. I've attached a spreadsheet. Thanks for taking the time to read.