rs 1 - 4 Homework Question 20, 3.4.33 HW Score: 50.24%, 1/.58 of 35 points Part 1 of 3 O Points: 0 of 1 Sa A walk-in clinic for emergency room services maintains Number of Patients per Frequency records of the number of patients it treats per day. The following table shows the frequency Day of the patient arrivals over the course of a 156-day period. 20 to under 40 40 to under 60 a. Calculate the approximate average number of patients per day. 60 to under 80 b. Calculate the approximate variance and standard 80 to under 100 deviation of the number of patients per day. 100 to under 120 (. . . a. Calculate the approximate average number of patients per day. I X (Round to one decimal place as needed.)