¥Let Ron play row one a fraction p of the time.
(Then he plays row two a fraction 1-p of the time.)
¥Let Charles play column one a fraction q of the time (and column two 1-q).
¥RonÕs expected winnings (if positive) or losses (if negative) will be a weighted average of the four possible outcomes, multiplying each by the fraction of the time it will occur.