Reading 3.1, problems => 13 - 17, due Sep 23rd

  1. mean= $2025.25 median= $2209 mode= none

  2. mean= $41.41 median= $40.76 mode= none

  3. mean= 3670 median= 3830 mode= 4090

  4. mean= 266 median= 266 mode= 260

  1. mean>median
  2. mean=median
  3. mean<median

Reading 3.2, problems => 5 - 10,14,24,

  1. Sample: 20, 13, 4, 8, 10 total= 55, mean= 11 (20-11)^2 + (13-11)^2 + (4-11)^2 + (8-11)^2 + (10-11)^2 = 144 144/(5-1) = 36 = s^2 s=6

population variance= 36 standard deviation= 6

  1. Sample: 83, 65, 91, 87, 84

total= 400, mean= 82

(83-82)^2 + (65-82)^2 + (91-82)^2 + (87-82)^2 + (84-82)^2 = 400 400/(5-1)= 100= s^2 s=10

population variance= 100 standard deviation= 10

  1. Population: 3, 6, 10, 12, 14 total= 45, mean= 9

(3-9)^2 + (6-9)^2 + (10-9)^2 + (12-9)^2 + (14-9)^2 = 80 36 + 9 + 1 + 9 + 25

80/5= 16=s^2 s=4

population variance= 16 standard deviation= 4

  1. Population: 1, 19, 25, 15, 12, 16, 28, 13, 6 total= 135, mean= 15

(1-15)^2 + (19-15)^2 + (25-15)^2 + (12-15)^2 + (16-15)^2 + (28-15)^2 + (13-15)^2 + (6-15)^2= 80 196 + 16 + 100 + 9 + 1 + 169 + 4 + 81= 576

576/9= 64=s^2 s=8

population variance= 64 standard deviation= 8

  1. Population: 6, 52, 13, 49, 35, 25, 31, 29, 31, 29 total= 300, mean= 30

(6-30)^2 + (52-30)^2 + (13-30)^2 + (49-30)^2 + (35-30)^2 + (25-30)^2 + (31-30)^2 + (29-30)^2 + (31-30)^2 + (29-30)^2= 576 + 484 + 289 + 361 + 25 + 25 + 1 + 1 + 1 + 1 = 1764

1764/9= 196=s^2 s=14

population variance= 196 standard deviation= 14

  1. Sanple: 4, 10, 12, 12, 13, 21 total= 72, mean= 12

(4-12)^2 + (10-12)^2 + (12-12^2 + (12-12)^2 + (13-12)^2 + (21-12)^2= 64 + 4 + 0 + 0 + 1 + 81= 150

150/6= 25=s^2 s=5

  1. range: 25 standard deviation: 8.4 minutes

  1. 6 seconds
  2. appropriate to use
  3. 95% d.93%
  4. 16%

population variance= 196 standard deviation= 14