Final answer:
The expected frequency of the train being on time over 20 days is 8.
Step-by-step explanation:
If the relative frequency of a train being on time is 0.4, you can expect it to be on time 40% of the time.
To find how often you could expect the train to be on time over 20 days, you can use the formula: Expected Frequency = Relative Frequency * Total Observations. In this case, the total observations would be 20.
So, the expected frequency of the train being on time over 20 days would be: 0.4 * 20 = 8.
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