Question

88. Refer to the Lincolnville School District bus data. Prepare a report on the mainte-nance cost for last month. Be sure to answer the following questions in your report.

a. Around what values do the data tend to cluster? Specifically what was the mean maintenance cost last month? What is the median cost? Is one measure more repre-sentative of the typical cost than the others?

b. What is the range of maintenance costs? What is the standard deviation? About 95% of the maintenance costs are between what two values?

ID	Maintenance Cost
10	4646
396	1072
122	9394
751	1078
279	1008
500	5329
520	4794
759	3952
714	3742
875	4376
600	4832
953	5160
101	1955
358	2775
29	5352
365	3065
162	3143
686	1569
370	7766
887	3743
464	2540
948	4342
678	3361
481	3097
43	8263
704	4218
814	2028
39	5821
699	9069
75	3011
693	9193
989	4795
982	505
321	2732
724	3754
732	4640
880	8410
193	5922
884	4364
57	3190
731	3213
61	4139
135	3560
833	3920
671	6733
692	3770
200	5168
754	7380
540	3656
660	6213
353	4279
482	10575
398	4752
984	3809
977	3769
705	2152
767	2985
326	4563
120	4723
554	1826
695	1061
9	3527
861	9669
603	2116
156	6212
427	6927
883	1881
168	7004
954	5284
768	3173
490	10133
725	2356
45	3124
38	5976
314	5408
507	3690
40	9573
918	2470
387	6863
418	4513

Answer 1

a) The mean and median maintenance cost last month are 4551.8875 and 4178.5 respectively. So, the data tend to cluster at around 4551.8875 or 4178.5.

The given Maintenance Cost data have positive skewness. Hence, the measure which is more representative of the typical cost is Median because the median is not affected much by the outlier value.

b. What is the range of maintenance costs? What is the standard deviation? About 95% of the maintenance costs are between what two values?

Ans: The the range of maintenance costs= Maximum-Minimum= 10575-505=10070.

The standard deviation (s)= 2332

About 95% of the maintenance costs are between the mean-2*s= -112.113 and mean+2*s=9215.888.