the sum of the first six terms of AP is 42.The Ratio of its 10 th term to its 30 th term is 1:3.Calculate first and thirteenth term of the Ap
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as usual , let the first term be a and common difference be d
thus A to Q,
S6 = 42
6/2(2a+5d) = 42
2a+5d=14------------------------1)
Again T10/T30=1:3
a+29d=3a+27d
a-d=0--------------------------------2)
From 1) & 2)
a=2&d=2
first term = 2
thirteen term = 2+24=26
Answer.........!!!!!!
thus A to Q,
S6 = 42
6/2(2a+5d) = 42
2a+5d=14------------------------1)
Again T10/T30=1:3
a+29d=3a+27d
a-d=0--------------------------------2)
From 1) & 2)
a=2&d=2
first term = 2
thirteen term = 2+24=26
Answer.........!!!!!!
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