Students working part-time at the Gabba walk around the stands selling hot dogs and meat pies on commission. They know that the weather affects the value of sales.On a cold night, they can make $893 in sales, while on a cool night they can make $719 in sales. On a mild night they can make $678 in sales.

If the probabilities for the first two scenarios are0.2 and0.34 respectively, then find the average value of sales in dollars.(two decimal places)