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:
Movies: 30/4 = $7.50/ticket
Concerts: 36.50/5 = $7.30
Concert tickets are $.20 cheaper.
There will be seven spaces between the 1st and the 8th post.
The distance between posts is 20 meters
The distance between the 1st and the 8th post is 20×7 = 140 metres
Gross pay = $2,759.00
Total deductions = 7.65%+12%+7% = 26.65% = 0.2665
By thumb rule, rent and other fixed expenses ≤ 28% of Monthly gross salary
Therefore,
Allowed housing and fixed expenses = 0.28*2,759 = $772.52
Then, a. is the correct answer.
Hi there!
So, 2.25x would represet the total amount of money spent for all the games.
2.25x + 2.50 = 9.25 would be the equation to represent this scenario.
Now to solve: Our goal is the get x alone. Subtract 2.50 (the price of the shoes) from both sides. 9.25 - 2.50 = 6.75.
We are now left with 2.25x = 6.75.
Finally, we divide both sides of the equation by 2.25, which leaves us with x = 3.
So you can bowl for a total of 3 games.
I hope I helped!
