Question 1011903
In an arithmetic progression , a4=7 and a9=22
a(1) + 3d = 7
a(1) + 8d = 22
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Subtract and solve for "d"::
5d = 15
d = 3
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Solve for "a(1)"::
a(1) + 3*3 = 7
a(1) = -2
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Find a14  = a(1) = 13*d
a(14) = -2 + 13*3
a(14) = 37
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Cheers,
Stan H.
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