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a new website had 150 subscribers in its first month. the designers hope to double the number of subscribers that sign up each month. if the designers get their wish, how many subscribers will sign up in all during the website's first year?

hint: if the number of subscriptions doubles each month, the common ratio of this geometric series is r=2. use the formula ∑ni=1a1(r)^i−1 = a1(1−rn) / 1−r to find the total number of subscribers that will be signed after 12 months.