3. The following table shows the numbers of patients classified as underweight, normal weight, overweight and obese according to their diabetes status.
If a patient is selected at random,
a) What is the probability that they are overweight?
b) What is the probability that they are obese and diabetic?
c) What proportion of the diabetics are obese?
d) What proportion of normal weight patients are not diabetic?
e) What proportion of patients are normal weight or underweight?
4. Approximately 30% of obese patients develop diabetes. If a physician sees 10 patients who are obese,  
a) What is the probability that half of them will develop diabetes?  
b) What is the probability that none will develop diabetes?  
c) How many would you expect to develop diabetes?
