Question 969852
What is the fourth term for the arithmetic sequence whose 10th term is 22 and 16th term is 40?
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Equations:
a + 9d = 22
a + 15d = 40
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Subtract and solve for "d"::
6d = 18
d = 6
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Solve for "a"::
a + 9d = 22
a + 54 = 22
a = -32
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Ans: a(4) = a + 3d = -32 + 3*6 = -14
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Cheers,
Stan H.
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