Subtraction gives completely wrong answers

I'm working on a tutorial (substituting C# for JS) for a camera that zooms out when the player jumps. Changing the variable to restrict the maximum zoom out had no effect, so I tested some stuff in the main camera's script and found an issue in this piece of code in the Update function:

         if (camZoom)
         {
             targetCurPos = player.transform.position.y;                    // get target's current Y position
             playerJumpHeight = targetCurPos - playerScript.groundPos;    // get latest jump height
             
             print ("STARTING POS " + playerScript.groundPos);
             print ("CURRENT POS " + targetCurPos);
             print (playerJumpHeight);

When I stand still, the starting and current positions both alternate between 0.74 and 0.7399999 and when subtracted, the answer alternates between - or + 5.0960464E-08. I have no idea where these answers are coming from. Am I missing something?