Answer:
5.71% probability that less than 60% of the sample would report that they had visited woodland in the previous year
Step-by-step explanation:
Problems of normally distributed samples are solved using the z-score formula.
In a set with mean and standard deviation , the zscore of a measure X is given by:
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
For a sampling propotion p in a sample of size n, we have that
In this problem, we have that:
What is the approximate probability that less than 60% of the sample would report that they had visited woodland in the previous year?
This is the pvalue of Z when X = 0.6. So
has a pvalue of 0.0571
5.71% probability that less than 60% of the sample would report that they had visited woodland in the previous year
Answer:
The required amount of mice is 11.82 gram.
Step-by-step explanation:
Given : Assuming that it is known from previous studies that σ = 4.5 grams. If we wish to be 95% confident that the mean weight of the sample will be within 3 grams of the population mean for all mice subjected to this protein diet.
To find : How many mice should be included in our sample?
Solution :
The formula used in the situation is
Where, z value at 95% confidence interval is z=1.96
gram is the mean of the population
gram is the standard deviation of the sample
Substituting the value, to find x sample mean
Therefore, The required amount of mice is 11.82 gram.
Answer:
B) 65°
Step-by-step explanation:
The formula for this would be x = 1/2 (a -b)
X being the angle you're trying to find
a being the larger arc and b being the smaller arc
Since a circle has 360°, and 245 is the larger arc, the smaller arc would be 115°
Now, just plug that into the equation; x = 1/2 (245-115)
This gives you x = 1/2 (130)
x = 65°
Answer: Ms. Shaw needs 6 fish tank
Step-by-step explanation: She need 6 fish tanks because each tank holds 3 fish and 3 x5 gives you the closest number. 1 fish will get it's own tank.
% of 120V = (150V/120V) x 100 = 125%
Therefore 150 volts is 125% of 120 volts