Answer:
(a) 20% to Longmont; 80% to Denver
(b) 20% to Longmont; 80% to Denver
Step-by-step explanation:
(a) The bus to Longmont is the first bus to arrive, only between 8:31 and 8:37, and again between 9:01 and 9:07. That is, for a total of 12 minutes every hour, the Longmont bus is the first to arrive. The probability of going to Longmont is 12/60 = 1/5 = 20%.
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(b) Same as for (a). As long as passenger arrival times are uniform within an hour, the probability is the same.