How to prove ΔPQR≅ΔTSR

1. the following set of data represents the number of waiting times in minutes from a random sample of 30 customers waiting for service at a department store. 4 5 7 10 11 11 12 12 13 15 15 17 17 17 17 17 18 20 20 21 22 22 23 24 25 27 27 31 31 32 a. determine the number of classes and class interval.

4. find the geometric mean of 4 and 12. 24 8

10 ! a train starts from grand city and travels toward belleville 388 miles away. at the same time, a train starts from belleville and runs at the rate of 47 miles per hour toward grand city. they pass each other 4 hours later. find the rate of the train from grand city.