Question 948130
Probability he catches the train 20 times in a row: 
P(catches all 20) = (0.97)^20 = 0.54379


probability he misses at least one train: 
P(misses at least one) = 1-P(catches all 20) = 1-0.54379 = 0.45621



Answer: 0.45621 or 45.621% (rough approximation)