For the first question, it's 20/60 (if it's a leap year, but tht doesn't rlly matter). That can be reduced to 1/3. However, there's also 5/60 which is reduced to 1/12. Since 1/3 is bigger than 1/12, he shouldn't expect to be able to get around at least 5 of the days. (But, I'm not exactly sure if this answer is correct. Just guess; there's 50% you'll get it correct and 50% you won't.)
For the second question, you first have to convert '56 out of 64 days' thing to percentage. You do 56/64 x 100 which is 5600/64. That equals to 87.5%. Since 90 > 87.5, the train is more reliable.
