Kevin horn is the national sales manager for national textbooks, inc. he has a sales staff of 40 who visit college professors all over the united states. each saturday morning he requires his sales staff to send him a report. this report includes, among other things, the number of professors visited during the previous week. listed below, ordered from smallest to largest, are the number of visits last week.

38
40
41
45
48
48
50
50
51
51
52
52
53
54
55
55
55
56
56
57
59
59
59
62
62
62
63
64
65
66
66
67
67
69
69
71
77
78
79
79

click here for the excel data file

(c) determine the first decile and the ninth decile. (round your answers to 1 decimal place.)

first decile
ninth decile
(d) determine the 33rd percentile. (round your answer to 2 decimal places.)

explain how you get the answer?