SOLUTION: The fourth term of an Arithmetic Progression (A.P) is one less than twice the second term. If the sixth term is 7, find the first term.

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Question 1141538: The fourth term of an Arithmetic Progression (A.P) is one less than twice the second term. If the sixth term is 7, find the first term.
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
General Term: A%2Bd%28n-1%29

Term n=4: A%2B3d
Term n=2: A%2Bd
Term n=6: A%2B5d=7


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fourth term of an Arithmetic Progression (A.P) is one less than twice the second term.
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A%2B3d=2%28A%2Bd%29-1
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A%2B3d=2A%2B2d-1
d=A-1

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Solve this system: system%28A%2B5d=7%2Cd=A-1%29