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anonymous
 one year ago
Find the doubling time of a quantity that is increasing by 9.8% per year.
anonymous
 one year ago
Find the doubling time of a quantity that is increasing by 9.8% per year.

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Haseeb96
 one year ago
Best ResponseYou've already chosen the best response.0lets suppose time = x then double time = 2x okay ???

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0t = log 2/log 1.08 = 9.006468 years

welshfella
 one year ago
Best ResponseYou've already chosen the best response.1yea where did you get that from?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Somebody help, I'm confused :(

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0i gave you the answer i cant give you the show work to

welshfella
 one year ago
Best ResponseYou've already chosen the best response.1oops guys I must apologise I had it the wrong way round! you divide the rate into 72 so it is 72 / 9.8 = 7.35 years

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0That's wrong @welshfella

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0@kinggg How did you get log 1.08? Where did the number 1.08 come from?

welshfella
 one year ago
Best ResponseYou've already chosen the best response.1how do you know its wrong?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0I entered it and it said answer is NOT CORRECT

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0@kinggg 9.006468 years is incorrect too

welshfella
 one year ago
Best ResponseYou've already chosen the best response.1i think the log formula is ln2 / ln(1.098)

welshfella
 one year ago
Best ResponseYou've already chosen the best response.1that gives 7.41 years

anonymous
 one year ago
Best ResponseYou've already chosen the best response.07.41 years is correct!

welshfella
 one year ago
Best ResponseYou've already chosen the best response.1Lets do it the long way teh suppose the principle is $100 we have double amount 200 = 100(1 + 0.098)^n (1.098)^n = 2 take logs: n ln 1.098 = ln n = ln 2 / ln1.098) = 7.41

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0are you doing Exponential growth, doubling time

welshfella
 one year ago
Best ResponseYou've already chosen the best response.1rounding that up its 8 years

anwaarullah
 one year ago
Best ResponseYou've already chosen the best response.08 years ,, let 100 be the investment so 100*1.098=,,,,,

welshfella
 one year ago
Best ResponseYou've already chosen the best response.1i guess that the interest is paid at the end of the year so that would make it 8.
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