Question

Financial analysts know that January credit card charges will generally be much lower than those of the month before. What about the difference between January and the next​ month? Does the trend​ continue? The accompanying data set contains the monthly credit card charges of a random sample of 99 cardholders. Complete parts​ a) through​ e) below.

a) Build a regression model to predict February charges from January charges.

​(Round to two decimal places as​ needed.)

Check the conditions for this model. Select all of the true statements related to checking the conditions.

A.

All of the conditions are definitely satisfied.

B.

The Randomization Condition is not satisfied.

C.

The Linearity Condition is not satisfied.

D.

The Equal Spread Condition is not satisfied.

Your answer is correct.

E.

The Nearly Normal Condition is not satisfied.

Your answer is correct.​

b) How​ much, on​ average, will cardholders who charged

​$2000 in January charge in​ February?

​

​(Round to the nearest cent as​ needed.)

​c) Give a​ 95% confidence interval for the average February charges of cardholders who charged

​$2000 in January . _____ and____.

​(Round to the nearest cent as​ needed.)

January   February
903.75   641.44
7215.49   4570.53
4236.94   2271.14
79.97   299.61
4039.03   1378.16
89.27   -120.87
3293.36   1929.59
2419.11   2607.52
83.95   144.97
6.42   392.79
0.00   40.44
564.05   295.68
2713.29   850.12
187.07   162.13
3263.17   2413.18
1523.21   956.09
1358.41   38.03
733.87   2656.39
75.07   64.95
70.21   -70.25
633.55   1862.68
1041.06   478.92
553.53   994.95
1016.33   774.41
1304.78   3369.45
249.29   5.54
48.71   96.97
873.07   890.97
485.14   485.29
616.39   1484.87
1573.84   889.25
422.92   391.46
770.25   323.46
56.61   0.00
1485.76   2253.57
495.19   389.82
1064.82   1066.01
509.94   131.46
5641.86   4945.74
5.49   5.49
871.17   591.41
1633.56   3364.55
92.28   85.98
670.21   1365.44
828.54   280.61
69.23   67.88
830.52   1056.92
2303.99   3319.41
270.27   14.12
210.57   160.78
1011.42   518.71
1043.81   2021.37
298.74   634.87
-30.01   0.00
1635.69   392.97
1733.75   1324.22
0.00   65.08
31.43   28.74
4.95   77.22
1087.53   892.47
26.85   28.99
120.32   32.21
2008.74   817.03
291.28   778.89
104.06   0.00
52.99   66.25
2839.67   1530.88
674.97   293.45
221.59   171.77
37.77   4.78
533.28   880.31
1931.25   1063.37
692.27   915.22
6797.95   5937.73
393.34   465.99
1309.27   303.23
796.94   497.25
0.00   266.32
1040.56   59.36
565.16   206.65
339.54   412.39
5274.03   5324.45
40.08   72.63
43.35   38.45
653.17   480.16
1071.62   416.66
2334.95   1788.53
91.51   175.14
1432.79   1107.71
720.43   307.63
28.59   24.16
980.43   1216.17
1575.99   1811.24
0.00   468.46
161.79   147.63
494.38   1993.93
533.48   934.27
462.02   114.45
1479.71   2094.74

Answer 1