What is the explicit rule for this geometric sequence?

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Question

What is the explicit rule for this geometric sequence?

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chrishogan · Answer

I've got the math all figured out. It's pretty simple now.

chrishogan · Answer

So to go from 4 to 4/5 you have to multiply 4 by 0.2, correct?

yuii · Answer

Yes.

chrishogan · Answer

So we need an equation now. $$g(n)=4*\frac{ 1 }{ 5 }$$ Alright easy, but to find where n will be, we need to know how many times we will multiply 1/5(0.2) to the sequenced numbers, I'll make it easy and tell you it's only one time at you go up the sequence. so now we have $$g(n)=4*\frac{ 1 }{ 5 }^{n-1}$$

chrishogan · Answer

so which answer choice looks like what I've just given you?

yuii · Answer

D?

chrishogan · Answer

Correct. Do you understand how I've gotten the answer?

yuii · Answer

Yes, thank you.

chrishogan · Answer

If you need help with anymore Reclusive sequences, let me know. Be sure to fan me as well. :)

yuii · Answer

Done.