Subtract The Lower Number From The Highest

I have name and a number in this

format: cell a1 Jones---56. In cell b1 I have another name i.e.,
Johnson---45. How can I subtract 45 from 56, take 60% of the difference
and in cell c3 show the following; Johnson---6. All numbers are to
rounded down to 0. The final result would look like this;
a1 Jones----56, b1 Johnson----45, c1 Johnson----6. I have other cells
with the same type of info in them. Example; a2 Smith----34, b2
Jones----78, c3 would show Smith----26.(rounded down) I always want to
subtract the lower number from the highest and take 60% of the
difference.