We have to define an interval about the mean that contains 75% of the values. This means half of the values will lie above the mean and half of the values lie below the mean.
So, 37.5% of the values will lie above the mean and 37.5% of the values lie below the mean.
In a Z-table, mean is located at the center of the data. So the position of the mean is at 50% of the data. So the position of point 37.5% above the mean will be located at 50 + 37.5 = 87.5% of the overall data
Similarly position of the point 37.5% below the mean will be located at
50 - 37.5% = 12.5% of the overall data
From the z table, we can find the z value for both these points. 12.5% converted to z score is -1.15 and 87.5% converted to z score is 1.15.
Using these z scores, we can find the values which contain 75% of the values about the mean.
z score of -1.15 means 1.15 standard deviations below the mean. So this value comes out to be:
150 - 1.15(25) = 121.25
z score of 1.15 means 1.15 standard deviations above the mean. So this value comes out to be:
150 + 1.15(25) = 178.75
So, the interval from 121.25 to 178.75 contains the 75% of the data values.
"inspiring that a person can say we own ourselves and no other person does"
Step-by-step explanation:
Answer:
0.0492
Step-by-step explanation:
Based on the tree diagram we need to tell the the probability that the test for lice returns a false positive. False positive means that the student has no lice but still the test shows a positive result.
So for this we have to first look for the branch, from the starting node, which shows that student has no lice. From the starting point, the upper branch represents the students that have lice and lower branch represents the students who have no lice. So, we will consider the lower branch with probability mentioned as 0.82
Now, the lower branch is divided into two branches further. We have to look for the branch which shows positive test result. This would be the upper branch with probability mentioned as 0.06.
The overall probability of this event is mentioned at the end of the branch which is 0.0492
This is the probability of the combined event: Student has no lice but tests shows positive result which is the False positive.
Thus, the probability that the test for lice returns a false positive is 0.0492
Answer:15+2.50(10x3)=x
Step-by-step explanation:
Mean : m = 2.2
Standard deviation: s = 0.3
m - 1 s = 2.2 - 0.3 = 1.9
m + 1 s = 2.2 + 0.3 = 2.5
For the normal distribution the values less than 1 standard deviation away from the mean account for 68.27 % of the set.
Answer: D ) 68 %
