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Isabella save to Nichols a day if she doubles the number of nickels she says each day how many days in cluding today will it take her to save more than 500

1 Answer

4 votes

Answer:

9 days

Explanation:

Given isabella saves a nickel a day.From this day onwards she kept on incresing the savings by doubling them.

Here it form's a geometric progression with first term(a) = 1 and common ratio (r) = 2

S(n) =
a((r^(n)-1 )/(r-1) )

Given condition is S(n) >500


(2^(n)-1 )/(2-1)>500


2^(n)>501

n ≥ 9

So it will take 9 days for her savings to be more than 500

User Roman Gonzalez
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