# Question #370a1

##### 1 Answer

Dec 8, 2016

About 18 hours.

#### Explanation:

The equation for 1st order decay is:

We get this using:

Taking natural logs of both sides of the decay equation:

Dec 8, 2016

About 18 hours.

The equation for 1st order decay is:

We get this using:

Taking natural logs of both sides of the decay equation: