Multiple choice

The given data shows the number of patients who consulted the doctors in a hospital during a month. What is the average number of patients consulted in a day? No. of patients No. of days 0 – 10 2 10 – 20 6 20 – 30 9 30 – 40 7 40 – 50 4 50 – 60 2 Total 30

  1. 13.0

  2. 19.6

  3. 22.9

  4. 28.7

  5. 24.0
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Calculate the midpoint of each class: 5, 15, 25, 35, 45, 55. Multiply by frequency: 5*2=10, 15*6=90, 25*9=225, 35*7=245, 45*4=180, 55*2=110. Sum = 860. Average = 860/30 = 28.66, which rounds to 28.7.

AI explanation

To find the average using the direct method for grouped data, first calculate the midpoints of each class interval: 5, 15, 25, 35, 45, and 55. Multiply each midpoint by its corresponding number of days to get the total patients per interval, which are 10, 90, 225, 245, 180, and 110. Adding these products gives a total of 860 patients across 30 days. Dividing 860 by 30 days yields an average of 28.7 patients per day.

Keep practicing — related questions