The easiest way to do this is to divide 225 by 3, so 225 / 3, and what you get as the sum, in this case it's 75, you would multiply the sum by 2, which equals 150, and that, would be Susan's share. So... 225 / 3 = 75. 75 * 2 = 150. $150 is the amount Susan gets. Hope this helps!
It’s beautiful because if you set up the problem as proportion and you put 3/106 over to you would have to multiply by 2×3 to get a six and 1×2 to get it to so it’s 2 mph