The tree diagram looks like this . . .A bag contains 4 Red and 3 Green balls.
Helen and Tony play a game where, starting with Helen,
they alternately draw a ball at random and do not replace it.
The game finishes when a Red ball is drawn.
It is decided that each player will receive, from the other units
if they draw the Red ball on the draw.
Construct a table for the random variable representing Helenís winnings:
thus if Helen draws a Red on the first draw,
if Tony draws it on the next, etc.
Calculate . How much, approximately, would Helen win in a series of 100 games?
. . .
Helen's winnings look like this:
She can expect to win an average of units per game.
In 100 games, she would win about: . units.