Getting ready for the big exam and I've come across a situation where I'm not sure how to get the answer. I have a Horizontal Curve with a known Radius, PI, External Distance (E), and Deflection Angle (I). The question gives a new E dimension and wants to know the new corresponding PC Station. If R stays the same and E increases, does the deflection angle I change? If so could you rearrange the equation E=R x [tan(I/2)] x [tan(I/4)] and solve in terms for I? Then with the new deflection angle could you solve for the new Tangent, T= R x tan(I/2), which in turn could be plugged into PC = PI - T and solve for new PC station using original PI? Thanks for any help or suggestions.