That means you want to take the 100, and give it to 2 people in a way that
one person has 4 shares, and the other person has 1 share. Then the
ratio of what the two people have is 4 to 1 .
Think about the shares . . . In order to give 4 shares to one guy and 1 share
to the other one, you need to cut up the 100 into 5 shares. So each share
has to be ( 100 / 5 ) = 20 .
Then the first guy gets 4 shares = (4 x 20) = 80 ,
and the other one gets 1 share = 20.
The ratio is 80/20 = 4/1 , and you've given out the whole (80 + 20) =100 .