Activity 2 Mean, Variance, and Standard Deviation of Discrete Random Variables 1. Read and answer the foolowing and make sure to show your solution. 1. The number of laptops sold per day at Laptop World is shown in the probability distribution below. X 19 20 21 22 23 P(X) 0.20 0.20 0.30 0.20 0.10 a, Find the mean, variance, and standard deviation of the distribution. Round off your answer to two decimal places. Mean = Variance = Standard Deviation =Activity 1 Discrete Probability Distributions (Random Variables and Probability Distribution) 1. Classify each random variable as either discrete or continuous. 1. The number of arrivals at an emergency room. 2. The weight of a box of cereal labeled "1818 ounces." 3. The duration of the next outgoing telephone call from a business office. 4. The number of kernels of popcorn in a 11-pound container. 5. The number of applicants for a job. Your Answer. 2. 3 52. Adrian's work schedule for next week will be released today. Adrian will work either 45, 40, 25, or 12 hours. The probabilities for each possibility are listed below: No. of Hours (X) 45 140 25 12 P(X) 0.25 0.30 0.35 0.10 a. Find the mean, variance, and standard deviation of the distribution. Round off your answer to two decimal places. Mean = Variance = Standard Deviation =Il. Three coins are tossed and the random variable X gives the number of tails. Determine the following: 1. X(HHT) 2. X(TTH) 3. X(HTH) 4. X(TTT) 5. Range Space Your Answer: 2. 3 4. 5