SOLUTION: If 15th and 11th term of an A.P are 3 and 23 respectively. Is 40 the term of the sequence ?

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Question 1040752: If 15th and 11th term of an A.P are 3 and 23 respectively. Is 40 the term of the sequence ?
Answer by stanbon(75887) About Me  (Show Source):
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If 15th and 11th term of an A.P are 3 and 23 respectively. Is 40 the term of the sequence ?
Equations:
a + 14d = 3
a + 10d = 23
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4d = -20
d = -5
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Then a = 3 -14(-5) = 73
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Is 40 the term of the sequence ?
Comment:: That is a strange question.
General term of the sequence is a(n) = 73 + (n-1)(-5)
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Solve, if possible::
73 + (n-1)(-5) = 40
5(n-1) = 33
n-1 = 33/5
n = 38/5
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No; 40 is not a term of the sequence.
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Cheers,
Stan H.