SOLUTION: the problem that i need help on states: Sebastian has a test that has 20 questions on it. The first question is worth one point, and each question after the first is worth four poi

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Question 193422This question is from textbook Algebra and Trignometry
: the problem that i need help on states: Sebastian has a test that has 20 questions on it. The first question is worth one point, and each question after the first is worth four points more than the question before it. What is the maximum score Sebastian can obtain? Please help asap! This question is from textbook Algebra and Trignometry

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Sebastian has a test that has 20 questions on it. The first question is worth one point, and each question after the first is worth four points more than the question before it. What is the maximum score
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It is an arithmetic series:
Formulas
S(n) = (n/2)(a+l) ; a is the 1st term and l is the last
a(n) = a(1) + (n-1)d
a(20) = 1 + 19*4 = 77
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S(20) = (20/2)(1 + 77) = 10*78 = 780
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Cheers,
Stan H.