In an analysis of healthcare data, ages have been rounded to the nearest multiple of 5 years. The difference between the true age and the rounded age is assumed to be uniformly distributed on the interval from -2.5yrs to +2.5yrs. The healthcare data are based on a random sample of 48 people. What is the approximate probability that the mean of the rounded ages within 0.25 years of the mean of the true ages?

The approximate probability that the mean of the rounded ages within 0.25 years of the mean of the true ages is P=0.766.

Step-by-step explanation:

We have a uniform distribution from which we are taking a sample of size n=48. We have to determine the sampling distribution and calculate the probability of getting a sample within 0.25 years of the mean of the true ages.

The mean of the uniform distribution is:

The standard deviation of the uniform distribution is:

The sampling distribution can be approximated as a normal distribution with the following parameters:

We can now calculate the probability that the sample mean falls within 0.25 from the mean of the true ages using the z-score:

a reflection across the x-axis , followed by the by a reflection across the y-axis , and then a scale dilation of 0.5 .

option (b) is correct

step-by-step explanation:

to find the solution of this system, we need to convert it into reduced row-echelon form. we have,

after applying row operations r2 -> r2/2 and r3 -> r3/3, we get,