Answer:
3000 students
Step-by-step explanation:
If 48% of the students are female, and there are 1440 female students, we can set up a percentage proportion, assuming x is the total amount of students.
We can use the cross products property to find the value of x.
Hope this helped!
Answer:
For the 99th percentile, we have X = 206 seconds.
Step-by-step explanation:
Problems of normally distributed samples can be 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.
In this problem, we have that:
99th percentile:
Value of X when Z has a pvalue of 0.99. So we use
For the 99th percentile, we have X = 206 seconds.