Discuss the below:
The question is based on the following information:
No. of Patients Alive
on each anniversary
Year of Treatment No. of Patients 1st 2nd 3rd
Treated
1991 75 60 56 48
1992 63 55 31
1993 42 37
Total 180 152 87 48
180 patients were treated for disease X from 1991 to 1993, and their progress was followed to 1994. The treatment results are given in the table. No patients were lost to follow-up.
Q: What is the probability of surviving for 3 years?