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What are the mean, variance, and standard deviation of these values? Round to the nearest tenth. 12, 13, 15, 4, 11, 12

Plz help

User PushpikaWan
by
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1 Answer

18 votes
18 votes

Answer:

i. Mean = 11.2

ii. Variance = 14.17

iii. Standard deviation = 3.76

Explanation:

i. Mean, m =
(sum of the values)/(number of the values)

=
(4+11+12+12+13+15)/(6)

=
(67)/(6)

= 11.2

The mean of the given data is 11.2

ii. Variance =
(sum(x_(i) - m)^(2))/(n-1)

where:
x_(i) is the value of the one observation, m is the sample mean and n is the number of data given.

=
([(4-11.2)^(2)+(11-11.2)^(2) + (12-11.2)^(2) + (12-11.2)^(2) + (13-11.2)^(2) + (15-11.2)^(2)] )/(6-1)

=
([51.84+0.04+0.64+0.64+3.24+14.44])/(5)

=
(70.84)/(5)

= 14.168

Variance = 14.17

iii. Standard deviation =
√(Variance)

=
√(14.17)

= 3.76

User Kqlambert
by
2.9k points