Intro Physics?

Question

A uniform plank of length 5.3 m and weight 215 N rests horizontally on two supports, with 1.1 m of the plank hanging over the right support (see the drawing). To what distance x can a person who weighs 453 N walk on the overhanging part of the plank before it just begins to tip?

Here is the drawing
http://www.webassign.net/CJ/09_14.gif

Answer 1

about 0.7 meters

215/5.3=40.566 N per meter
4.2 meters are for counterbalance
so that is a total of 170.377 N
the average distance from the fulcrum is 2.1 meters
total counterbalance force =357.792N

the 1.1 m portion id 44.623 N at an average distance of .55m
24.542 N to subtract from the counterbalance force

332.835/453=.735 m