SOLUTION: The 14th term of a linear sequence is 96 while the 25th term is 173. Find the
a) 19th term
b) sum of 13th and 56th terms
c) sum of the first twenty terms
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-> SOLUTION: The 14th term of a linear sequence is 96 while the 25th term is 173. Find the
a) 19th term
b) sum of 13th and 56th terms
c) sum of the first twenty terms
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Question 934750: The 14th term of a linear sequence is 96 while the 25th term is 173. Find the
a) 19th term
b) sum of 13th and 56th terms
c) sum of the first twenty terms Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! The 14th term of a linear sequence is 96 while the 25th term is 173.
14th:: a + 13d = 96
25th:: a + 24d = 173
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Substitute and solve for "d":
11d = 77
d = 7
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Solve for "a":
a + 13*7 = 96
a + 91 = 96
a = 5
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Find the
a) 19th term:: a + 18d = 5+18*7 = 131
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b) sum of 13th and 56th terms
a+12d + a+55d = 2a + 67d = 10+469 = 479
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c) sum of the first twenty terms
I'll leave that to you.
Cheers,
Stan H.
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