Restoring this lost corner by three-point control would be accomplished by single proportioning the latitude position on the north/south line between found corners and then using the record distance from the east.

Here is the retracement data for our sample problem.

Let's begin recording this on the traverse computation sheet. Proceed just as we've done in single and double proportion by entering the beginning an ending points of each leg of the traverse then, computing the latitudes and departures.