Step 1 :The problem is asking for the mean, variance, and standard deviation of the number of students who do their homework on time in a class of 250 students, given that approximately 54% of students do their homework on time.
Step 2 :The mean of a binomial distribution is given by np, where n is the number of trials (in this case, the number of students) and p is the probability of success (in this case, the probability that a student does their homework on time).
Step 3 :The variance of a binomial distribution is given by np(1-p), where n is the number of trials, p is the probability of success, and 1-p is the probability of failure.
Step 4 :The standard deviation is the square root of the variance.
Step 5 :Given that n=250 and p=0.54, we can calculate the mean, variance, and standard deviation.
Step 6 :Mean = np = 250 * 0.54 = 135
Step 7 :Variance = np(1-p) = 250 * 0.54 * (1 - 0.54) = 62.1, which is approximately 62 when rounded to the nearest whole number.
Step 8 :Standard Deviation = \(\sqrt{Variance}\) = \(\sqrt{62.1}\) = 7.88, which is approximately 8 when rounded to the nearest whole number.
Step 9 :\(\boxed{\text{Final Answer: The mean is 135, the variance is approximately 62, and the standard deviation is approximately 8. Therefore, the correct answer is (d.) Mean =135, Variance =62, Standard Deviation =8.}}\)