Problem 3.0.9 McMaster University students scored an average of 145 and standard deviation of 3 on IQ Test. University of Toronto students scored an average of 150 and standard deviation of 0 on IQ test. Assume that the scores of McMaster University students and University of Toronto students are normally distributed. (a) What percent of McMaster University students scored less than 140? (b) 'What percent of University of Toronto students scored less than 140'? Problem 3.0.10 Average response time for emergency calls in a police department is 10.5 minutes with a population standard deviation of 2.3 minutes. Assume that response time is normally distributed. (a) One police department claims that the maximum response time is 12 minutes. what is the probability that the police departments estimation about the time does not happen. (b) If the police department wants to give the estimation about the time with 95% condence, what would be the time? Problem 3.0.11 The Hamont tire company has found that the life of their tires follows a normal curve with average of 40000km and a standard deviation of 10000km. (a) What percentage of the tires will have a life of less than 50000km? (b) What percentage of the tires will have a life of more than 50000km? (c) 'What percentage of the tires will have a life of less than 20000km? (d) 'What percentage of the tires will have a life between 40000km and 50000km? Problem 3.0.12 The Hamont tire company has found that the life of their tires follows a normal curve with average of 40000km and a standard deviation of 10000km. (a) 30% of the tires have life of more than how much? (b) 60% of the tires have life of less than how much? Problem 3.0.13 Studies reveal that welfare recipients spend an average of $45 per week on food with a standard deviation of $8. The food expenditure pattern is normally distributed. (a) 'What percent of recipients spent atleast $30 on food per week '? (b) What percent of recipient spent atmost $25 on food per week ? (c) 70% of recipient spend more than how much '? Problem 3.0.14 The average length of hockey sticks produced at an assembly line is 165 cm with a standard deviation of 5 cm. Furthermore, it is known that the length of hockey sticks is normally distributed. (a) 'What is the probability that the length of hockey sticks is greater than 170 cms? (b) 'What is the probability that the length of hockey sticks is smaller than 158 cms? (c) 'What is the probability that the length of hockey sticks is between 160 cuts and 174 cms? Problem 3.0.15 The average length of hockey sticks produced at an assembly line is 165 cm with a standard deviation of 5 cm. Furthermore, it is known that the length of hockey sticks is normally distributed. (a) 15% of the hockey sticks are less than how many cms? (b) 20% of the hockey sticks are longer than how many cms
