18. Please answer questions 18-19 using the following information:

Question

Class Scores Frequency - f
Lower limit < score < upper limit
20-30 6
30-40 10
40-50 12
50-60 8
60-70 4

What is the probability that a selected observation is between 40 and 50?

(Points: 5)
0.25
0.30
0.40
0.65

19. What is the probability that a selected observation is greater than 39, but less than 60? (Points: 5)
0.20
0.40
0.30
0.50