Thanks for this,
But it seems I have made a mistake,
Rephrased:
We are looking for L87.75
x=87.75 y=L87.75
x1=87 y1=L87
x2=88 y2=L88
(87.75-87)/(88-87) = (L87.75-L87)/(L88-L87)
=> L87.75 = L87+0.75(L88-L87)
calculating gives:
L87.5 = 14280+075(11874-14280)
=12475.5
... which actually is the same as the solution
My bad - i thought this lead to a difference - thanks
Last edited: Apr 11, 2018