Answer:
1/3
Step-by-step explanation:
Interval Frequency
20-29 2
30-39 1
40-49 4
50-59 2
60-69 8
70-79 7
80-89 3
90-99 3
Now, we can calculate the probability of a candidate chosen at random having 50 to 69 marks:
Frequency of having 50-69: 10
Total frequencies: 30
10/30=1/3
1/3 is the probability that a candidate chosen at random had 50-69 marks.