Question

On average, 75% of the days in Henderson county are sunny, with little or no cloud cover. Describe a model that you could use to find experimental probability of sunny days each day for a week in Henderson county.

Answer 1

One possible model is:

You could place 3 red marble and 1 blue marble in a bag. The probability of drawing a red marble would be 3/4, which is 75%; this means red marbles would be sunny days and blue marbles would be cloudy days.

Each draw out of the bag would represent one day of the week. Draw a marble 7 times, replacing it after each draw. This would represent the weather for the days of the week.

Answer 2

We have that the probability to have a sunny day is approximately 75%. Hence, the probability that we have 2 sunny days in a row is 75%* 75% (we are kind of assuming that the weather of a day plays no role on the weather of the next day, which is not completely true). That is because for it to 2 sunny days, both days have to be sunny. It is analogous to a coinflip; the chance we get 2 heads is 50%*50%, the chance we get 3 heads is 50%*50%*50% and so on. Hence, we have that the chance that a week is sunny in the county is 75% to the seventh power. This yields that the chance is around 13.3%