看不太懂題目跟如何解題 謝謝
190. An infinite sequence of positve intergers is called an "alpha sequence"
if the number of even integers in the sequence is finite. If S is an
infinite sequence of positve integers, is S an alpha sequence?
(1) The first ten integers in S are even.
(2) An infinite number of integers in S are odd.
242. On Jane's credit card account, the average daily balance for a 30-day
billig cyclei is the average(arithmetic mean) of the daily balances at
the end of each of the 30 days. At the beginning of a certain 30-day
billing cycle, Jane's credit card account had a balance of $600. Jane
made a payment of $300 on the acount during the billing cycle. If no
other amounts were added to or subtracted from the account during the
billing cycle, what was the average daily balance on Jane's account for
the billing cycle?
(1) Jane's payment was credited on the 21st day of the billing cycle.
(2) The average daily balance through the 25th day of the billing cycle
was $540
thx
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