Nope, 642.7 lbs from 2 to 1
10650/(210-94)*((210-165)-(210-172))
Try it from first principals.
Lets say x = weight in hold 1 and y = weight in hold 2
You know that 94x + 210y = 10650*172
and
x + y = 10650
So you can work out x and y
Then work out x and y when 94x + 210y = 10650*165
take one x from the other and bob's your uncle.
A bit of algebraeic manipulation and you get the equation at the top.
Hope that helps