Suppose the following are the city driving gas mileages of a selection of sport utility vehicles (SUVs). 19, 20, 19, 20, 18, 21, 17, 19, 24, 23, 21, 21, 17, 20, 20, 18 (a) Find the sample standard deviation (rounded to two decimal places). (b) In what gas mileage range does Chebyshev's inequality predict that at least 75% of the selection will fall

Respuesta :

Answer:

answer below

Step-by-step explanation:

from the question the

mean = ∑x/n

∑x = 317

n = 16

mean = 19.8125

x           x-Ц           x-Ц²

19       -0.8125      0.66015625

20       0.1875      0.03515625

19          -0.8125      0.66015625

20         0.1875      0.03515625

18         -1.8125       3.28515625

21          1.1875        1.41015625

17           -2.8125      7.91015625

19           -0.8125      0.66015625

24           4.1875       17.53515625

23            3.1875      10.16015625

21           1.1875        1.41015625

21            1.1875        1.41015625

17             -2.8125      7.91015625

20          -0.8125      0.66015625

20           -0.8125      0.66015625

18            -1.8125       3.28515625

∑(x-Ц)² = 56.44

s.d = 1.9

b.

19.81 + 2*1.9= 23.61

19.81-2*1.9 = 16.01

=