Answer:
a) Time spent, x (minute): 50 < x ≤ 60
b) Time spent, x (minute): 20 < x ≤ 30
Explanation:
a) The modal class is the class interval with the highest frequency in a frequency table which is 21 (right column)
b) Find the total amount of Frequency:
12 + 18 + 11 + 9 + 8 + 21 = 79
to find mid number through the data set divided by 2:
79 / 2 = 39.5
so add up the frequency till you reach 39.5 (max)
12 + 18 = 30
30 + 11 = 41 this passes through 39.5 so the median is in the 3rd row