Statistics for business

Relative Time (in Minutes) Frequency 0 but less than 5 0.37 5 but less than 10 0.22 10 but less than 15 0.15 15 but less than 20 0.10 20 but less than 25 0.07 25 but less than 30 0.07 30 or more 0.02 a. What is the width of each class? b. If 1,000 calls were randomly sampled, how many calls lasted under 10 minutes? c. If 100 calls were randomly sampled, how many calls lasted 15 minutes or longer? d. If 10 calls lasted 30 minutes or more, how many calls lasted less than 5 minutes? e. What is the cumulative relative frequency for the percentage of calls that lasted under 20 minutes? What is the cumulative relative frequency for the percentage of calls that lasted 10 minutes or more? R. If 100 calls were randomly sampled, of them would have lasted at least 15 minutes but less than 20 minutes. h. If 100 calls were sampled, of them would have lasted less than 15 minutes. i. If 100 calls were sampled, of them would have lasted 20 minutes or more