Answers

The Brainliest Answer!
2014-10-01T00:04:51+05:30

This Is a Certified Answer

×
Certified answers contain reliable, trustworthy information vouched for by a hand-picked team of experts. Brainly has millions of high quality answers, all of them carefully moderated by our most trusted community members, but certified answers are the finest of the finest.
For 67% decay,
Remaining = 100% - 67% = 33% = 0.33
0.33 =  e^{-t1. ln(2)/20}
⇒ ln(0.33) = -t1. ln(2) / 20
⇒t1 = -[ ln(0.33)×20÷ln(2) ]
⇒t1 = 31.99 min

Similarly
For 33% decay,
Remaining = 100% - 33% = 67% = 0.67
0.67 =  e^{-t2. ln(2)/20}
⇒t2 = -[ ln(0.67)×20÷ln(2) ]
⇒t2 = 11.55 min

Difference = t1 - t2 = 20.44 minutes
1 5 1