suppose that of the 155 patients who visited doctor baptiste's office this week, 51 had high cholesterol, 45 had hypertension and 71 had neither high cholesterol nor hypertension. 

Let C be the number of patients with high cholesterol and H the number with hypertension. How many patients had both high cholesterol and hypertension, |C intersect H|?

What is the probability that a randomly chosen patient had high cholesterol and hypertension, P(C intersect H)?

What is the probability that a randomly chosen patient had either high cholesterol or hypertension, P(C or H)?