.
Notice that = 2048 = .
It means that 60 hours = 11 doubling periods.
Hence, one doubling period is = 5 hours.
And a quadruple period is twice of it, i.e. hours = 10 hours.
Solved.
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See the lesson
- Radioactive decay problems
in this site - - - to make your horizon W I D E R.
Also, you have this free of charge online textbook in ALGEBRA-I in this site
- ALGEBRA-I - YOUR ONLINE TEXTBOOK.
The referred lesson is the part of this online textbook under the topic "Logarithms".
Save the link to this online textbook together with its description
Free of charge online textbook in ALGEBRA-I
https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson
to your archive and use it when it is needed.