Let’s say that you saw dark clouds today. There is a 70% cha…

Let’s say that you saw dark clouds today. There is a 70% chance of seeing dark clouds today given that it will rain tomorrow (from historical data). There is a 20% chance of seeing dark clouds today given that it won’t rain tomorrow (again from historical data). There is a 50% chance of seeing dark clouds regardless of whether or not it will rain. The current knowledge without any extra information is that there is a 30% chance of rain tomorrow. What is the updated probability of rain tomorrow given that we saw dark clouds today? Hint: Let A be the event that it will rain tomorrow and B be the event that you observed dark clouds today. You need to find P(A|B). Use the tree diagram and Bayes theorem.

A student proposes that left-handedness is a recessive trait…

A student proposes that left-handedness is a recessive trait and is hidden in much of the human population. A survey of his class of 36 students finds that 9 students are left-handed. Using the Hardy-Weinberg formula, what would be the expected allelic and genotypic frequencies in this theoretical population?