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September 30, 2014

September 30, 2014

Posted by **Dee** on Sunday, November 17, 2013 at 4:10pm.

____hr

- college algebra -
**Steve**, Sunday, November 17, 2013 at 4:14pmIf there was 40% more, then that's 1.4 times what's there now.

So, starting with an original amount of 1, there is now 1/1.4 of it left.

(1/2)^(t/8.4) = 1/1.4

Now just solve for t hours.

Note: It will be less than 8.4, since 8.4 hours ago, there was 100% more.

- college algebra -
**Dee**, Monday, November 18, 2013 at 9:24pmnot sure how to find the t, tried using the log approach but can't get the right answer.

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