Help with part (f) please!

In the following probability distribution, the random variable x represents the number of activities a parent of a K to 5thgrade student is involved in. Complete parts (a) through (f) below. x | 0 | 1 | 2 | 3 | 4 121 P(x) | 0.407 | 0.196 | 0.126 | 0.169 | 0.102 01234 01234 01234 01234 (c) Compute and interpret the mean of the random variable x, The mean is 1.363 activities. (Type an integer or a decimal. Do not round.) Which of the following interpretations of the mean is correct? A. The observed value of an experiment will be equal to the mean of the random variable in most experiments. B. As the number of experiments decreases, the mean of the observations will approach the mean of the random variable. .9 C. As the number of experiments increases, the mean of the observations will approach the mean of the random variable. D. The observed value of an experiment will be less than the mean of the random variable in most experiments. (d) Compute the standard deviation of the random variable x. The standard deviation is 1.4 activities. (Round to one decimal place as needed.) (6) What is the probability that a randomly selected student has a parent involved in three activities? The probability is 0.169 . (Type an integer or a decimal. Do not round.) (f) What is the probability that a randomly selected student has a parent involved in three or four activities? The probability is . (Type an integer or a decimal. Do not round.)