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Aliyah plays an online learning game where she earns 10 stars for each question she answers correctly. When Aliyah

finishes playing the game, she has a total of 570 stars.
Write an equation for this arithmetic sequence in the form an = a, + d(n-1) that can be used to model the number
of stars Aliyah ears when she answers n questions correctly.

1 Answer

2 votes

Answer:

CASE I:


a_1 = 10


a_n =a_1+10(n-1)

CASE II:


a_1 = 570


a_n =a_1+10(n-1)

Explanation:

CASE I: We start counting when Aliyah starts the game.

For the first question she answers Aliyah earns 10 points; therefore,


a_1 = 10.

And for every additional nth answer, Aliyah earns 10 additional points; therefore,


a_n = a_1+10(n-1)


\boxed{a_n =10+10(n-1)}.

CASE II: We start counting after Aliyah finishes the first game.

In which case


a_1 = 570

and therefore,


\boxed{a_n = 570+10(n-1)}

User Shaun Scovil
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