SOLUTION: The half-life of Erbium-171 is 7.5 hours. What is the hourly decay rate? Express the result to four decimal places.

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Question 1128753: The half-life of Erbium-171 is 7.5 hours. What is the hourly decay rate? Express the result to four decimal places.
Answer by greenestamps(13200) About Me  (Show Source):
You can put this solution on YOUR website!


Let x be the fraction remaining after one hour. Then, since the half-life is 7.5 hours,

x%5E7.5+=+0.5
x+=+%280.5%29%5E%281%2F7.5%29+=+0.9117 to 4 decimal places.

The amount remaining decreases by a factor of 0.9117 per hour. That means the fraction that remains at the end of each hour is

1-0.9117 = 0.0883

I don't know which of those two numbers is your definition of "hourly decay rate".