# MATHEMATICS

31. A variable whose value is a numerical outcome of a random phenomenon is called a random variable. biased. a parameter. a random sample.

32. A physician observes the number of lesions on subjects who had regularly used tanning salons. Let X be the number of lesions observed. The physician found that X had the following probability distribution. Value of X 0 1 2 3 4 Probability 0.05 0.1 0.25 0.30 0.30 P(X > 3) has value 0.7. 0.4. 0.6. 0.3.

33. Based on data from the USDA, we define the following probability model for the number X of different pesticides detected in fresh produce. X 0 1 2 3 4 5 or more Probability 0.43 0.17 0.14 0.08 0.06 0.12 The numerical value for the probability P(X [removed] –2.62 is 0.0044. 0.0047. 0.9956. 0.9953. 35. The pH measurements of water specimens from various locations along a given river basin are Normally distributed with mean 8 and standard deviation 0.3. What is, approximately, the probability that the pH measurement of a randomly selected water specimen is greater than 8.2? 0.2475 0.7525 0.2525 0.7475

36. The pH measurements of water specimens from various locations along a given river basin are Normally distributed with mean 8 and standard deviation 0.3. Three-quarters of the pH measurements in this river basin are greater than 8.402. 8.202. 7.798. 8.450.

37. A researcher is interested in the lengths of Salvelinus fontinalis (brook trout), which are known to be approximately Normally distributed with mean 80 centimeters and standard deviation 5 centimeters. To help preserve brook trout populations, some regulatory standards need to be set limiting the size of fish that can be caught. The probability of catching a brook trout less than 72 centimeters in length is 0.9452 0.6255. 0.0548. 0.3745. 38. The distribution of total body protein in adult men with liver cirrhosis is approximately Normal with mean 9.8 kg and standard deviation 0.1 kg. Twenty-five percent of adult men with cirrhosis have a total body protein of at least 9.87 kg. 9.70 kg. 9.73 kg. 9.60 kg.