<h3>
Answer: 0.57</h3>
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Explanation:
The notation
P( Take the bus | Junior)
is the same as writing
P( Take the bus given Junior)
I replaced the vertical bar with the word "given".
Since we're given that the person is a Junior, this means we only focus on the Juniors. There are 13+20+2 = 35 Juniors and 20 of them take the bus.
20/35 = 0.5714 approximately which rounds to 0.57
This says about 57% of the Juniors take the bus.
