Question 925651
Which is the iterative rule for the sequence: 15.5, 13, 10.5, 8, 5.5, 3, …? 
(Points : 1)
 a. an = 15.5 − 2.5n
 b. an = 18 – 2.5n
 c. an = 15.5 + 2.5n
 d. an = 18 + 2.5n
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You know the 1st term has n = 1
Looking at the 1st term (15.5) you can see that "a" would be less than
15.5 for n = 1. So "a" is not the answer.
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"c" cannot be the answer because when n = 1, 15.5+2.5n is greater than 15.5.
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"d" is greater than 18 for n = 1 so "d" is not the answer.
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Ans: The answer is "b"
Check it out.
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Cheers,
Stan H.
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