A program is tested and the total number of errors is estimated as 16. The program is then seeded with 20 deliberate errors and further testing is then carried out until all 20 seeded errors have been...

A program is tested and the total number of errors is estimated as 16. The program

is then seeded with 20 deliberate errors and further testing is then carried out until

all 20 seeded errors have been found.

(a) If no new (previously undetected) errors are found during this further testing to

find all seeded errors, calculate the probability that the program is error-free

after this further testing.

(b) How many seeded errors would have to be put into the program and then

detected to achieve a 98% probability that the program is error-free?