Answer: The 95% confidence interval is approximately (55.57, 58.43)
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Explanation:
At 95% confidence, the z critical value is about z = 1.960 which you find using a table or a calculator.
The sample size is n = 17
The sample mean is xbar = 57
The population standard deviation is sigma = 3
The lower bound of the confidence interval is
L = xbar - z*sigma/sqrt(n)
L = 57 - 1.960*3/sqrt(17)
L = 55.5738905247863
L = 55.57
The upper bound is
U = xbar + z*sigma/sqrt(n)
U = 57 + 1.960*3/sqrt(17)
U = 58.4261094752137
U = 58.43
Therefore the confidence interval (L, U) turns into (55.57, 58.43) which is approximate.
Answer:
S={WG, WE, WM, YG, YE, YM, BG, BE, BM}
Step-by-step explanation:
There are three possible color choices for the game room (White, Yellow or Blue), and three possible choices for the entertainment center (Gray, Ebony or Maple). This means that there are 9 possible outcomes, therefore, the sample space for the experiment is:
S={WG, WE, WM, YG, YE, YM, BG, BE, BM}
Answer:
(a) 13.85 °C
Step-by-step explanation:
The temperature difference is a decaying exponential function of time. Here, it decreases from an initial difference of 15 °C to 10 °C after 25 minutes. So, that temperature difference can be modeled as ...
ΔT = 15(10/15)^(t/25)
We want to find the value of this at t=55. It is ...
ΔT = 15(2/3)^(55/25) ≈ 6.15
This is the amount the temperature of the drink is below room temperature.
drink temperature = (20 - 6.15) °C = 13.85 °C
The temperature of the drink after 55 minutes is about 13.85 °C.
Answer:
A) 99.7% of people have an IQ between 64 and 136.
B) 5% of people have an IQ score less than 76 or greater than 124.
C) 16% of people have an IQ score greater than 112.
Step-by-step explanation:
The Empirical Rule tells us that, in a normal or 'bell-shaped' distribution, 68% of the data is one standard deviation from the mean, 95% of the data is two standard deviations from the mean, and 99.7% of the data is three standard deviations from the mean.
A) 64 and 136 are 3 standard deviations away from the mean, so 99.7% of people have an IQ between 64 and 136.
B) 76 and 124 are 2 standard devations away from the mean, but the answer is asking what percentage is not between them. 100% - 95% gives us 5%.
C) 112 is one standard deviation away from the mean. If we want to find the percentage greater, then we can do 100% - 50% (as 112 is to the left of the mean), then we can take half of 68 to get 34%, and after subtracting 50% and 34% from the 100%, we get 16%.
Answer:
D. 73°
Step-by-step explanation:
The inside angles of a triangle always equal 180° so if we know that a right angle is already 90° we only need one more angle to know all of them:
1. 90° + 17° + ?° = 180
2. 90° + 17° = 107°
3. 180° - 107° = 73°
4. 90° + 17° + 73° = 180
5. XD
