Problem:
Marley practices exactly one sport each day of the week. She runs three days a week but never on two consecutive days. On Monday she plays basketball and two days later golf. She swims and plays tennis, but she never plays tennis the day after running or swimming. Which day of the week does Marley swim?
Answer Choices:
A. Sunday
B. Tuesday
C. Thursday
D. Friday
E. Saturday
Solution:
Marley plays basketball on Monday and golf on Wednesday. Because she cannot run three of the four consecutive days between Thursday and Sunday, she must run on Tuesday. From Thursday to Sunday she runs, swims, and plays tennis, but she cannot play tennis the day after running or swimming. So she must play tennis on Thursday. She must swim on , and run on Friday and Sunday, so that she does not run on consecutive days.
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