Answer:
A
Step-by-step explanation:
Answer:
A task time of 177.125s qualify individuals for such training.
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

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. Subtracting 1 by the pvalue, we This p-value is the probability that the value of the measure is greater than X.
In this problem, we have that:
A distribution that can be approximated by a normal distribution with a mean value of 145 sec and a standard deviation of 25 sec, so
.
The fastest 10% are to be given advanced training. What task times qualify individuals for such training?
This is the value of X when Z has a pvalue of 0.90.
Z has a pvalue of 0.90 when it is between 1.28 and 1.29. So we want to find X when
.
So




A task time of 177.125s qualify individuals for such training.
Answer:
15.87% is the chance that Scott takes more than 4.25 minutes to solve a problem at an academic bowl.
Step-by-step explanation:
We are given the following information in the question:
Mean, μ = 4 minutes
Standard Deviation, σ = 0.25 minutes
We standardize the given data.
Formula:
P(more than 4.25 minutes to solve a problem)
Calculation the value from standard normal z table, we have,
Thus,15.87% is the chance that Scott takes more than 4.25 minutes to solve a problem at an academic bowl.