Answer:
0.016062.
Step-by-step explanation:
Assume that the population is normal:
~(,
2
) = (1185, 702
).
Then the distribution of the sample mean
̅ =
1 + 2 + 3 + ⋯ + 100
100
is exactly normal with mean
̅= (̅) = = 1185 hours
and standard deviation
̅= (̅) =
√
=
70
√100
= 7 hours.
The standardized variable
=
̅ − ̅
̅
=
̅ − 1185
7
Is distributed as (0,1).
The following value of corresponds to the value ̅= 1200 of ̅:
=
̅−̅
̅
=
1200−1185
7
= 2.142857.
Therefore,
(̅ ≥ 1200) = (
̅ − ̅
̅
≥
1200 − ̅
̅
) = ( ≥
1200 − 1185
7
) = ( ≥ 2.142857) =
= 1 − ( < 2.142857) = 1 − 0.983938 = 0.016062,
because using the command
= NORM. S.DIST(2,142857; TRUE)
from Microsoft Excel we can see that
= 2.142857
gives
( < 2.142857) = 0.983938.
Only rarely, just over one time in a hundred tries of 100 light bulbs, would the average life exceed 1200 hours
Answer:
y=6x-9
Step-by-step explanation:
G(x) = 3x-2
g(-2) = 3(-2) - 2
g(-2) = -6-2
g(-2) = -8
g(0) = 3(0)-2
g(0) = 0-2
g(0) = -2
g(5) = 3(5)-2
g(5) = 15-2
g(5) = 13
Answer:
(x-1) ^2 + (y+4)^2 = 4
Step-by-step explanation:
The equation of a circle can be written as
(x-h) ^2 + (y-k)^2 = r^2 where (h,k) is the center and r is the radius
(x-1) ^2 + (y- -4)^2 = 2^2
(x-1) ^2 + (y+4)^2 = 4