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Your exponential formula for decay of the memory is
W(t) = .
Based on the condition, you write the equation for t as you read your text
10000 = .
Next, you divide both sides by 20000
0.5 = .
Now, you take log base 10 of both sides
log(0.5) = t*log(0.904)
which gives you an expression for time "t"
t =
Next you use your calculator and get
t = 6.868 years. ANSWER
ANSWER. 6 years and 316 days.
Solved, answered, explained and completed.
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To see many other solved problems on exponential growth/decay, look into the lessons
- Population growth problems
- Radioactive decay problems
- Carbon dating problems
- Bacteria growth problems
- A medication decay in a human's body
- Problems on appreciated/depreciated values
- Inflation and Salary problems
in this site.
Also, you have this free of charge online textbook in ALGEBRA-I in this site
- ALGEBRA-I - YOUR ONLINE TEXTBOOK.
The referred lessons are 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.
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