Half Life Formula & Example

Learn the formula for half life as well as see an example in this free math video tutorial by Mario's Math Tutoring.

0:09 Formula for Calculating Half Life
0:38 Example 1 Story (Word) Problem
1:21 Taking the Logarithm of Both Sides to Solve For t
2:05 Using Change of Base Formula

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[elmer]

This was so helpful. Thank you for efficiently explaining this and using an example. Perfect video.

This has been great for me, I have struggled for hours and it is just perfect. i will be looking for more...
Thank you

[OShawna]

Thanks for helping me with my MCAT math ❤🎉

[EmperorSteel]

This has helped a ton. I think I struggled with computing it, but after finally trying, I got to the same conclusion. Thanks for your help

[arielbryant]

Than k you so much. You have no idea how long I have been trying to figure this out and checking different websites and videos. I have been struggling with math this year and usually I pick it up fast. I just had a moment of OH MY GOD I did it!

[cgreer]

Wow, a video that finally helps me understand. Thank you!

[elflonghand]

Thank you this helped a lot for my test tomorrow!

[SkyLLer]

Gordon doesn't need to hear all this he's a highly trained professional

[turntechhh]

thank you so so much!!!! now i feel much more prepared for my test tomorrow :-)

[jaxondoering]

This helped me out much. Can't thank you enough.

[Asmrssss]

Best simple explanation I’ve ever heard!

[reembeem]

may god bless your heart, wonderful teaching method

[soohyeonpyo]

Thank you so much for the efficient video:)

[mariahdougherty]

How would one calculate the natural log WITHOUT calculator?

[m_doggy]

Yes2x thank you Soo much sir for helping find another solution for solving it, because my scientific calculator doesn't have the ability of that other log. YAY I'm gonna ace my test on monday

[FaultyRedstone]

Thank you! This was exactly what I needed.

[sonusingh-ixyx]

Hey I'm from India
I really impressed your teaching style 👌

[huyanhle]

Hi Mario and everyone,

Could you please help me with this following question

Radioactive materials are considered to be relatively safe when their
activity has fallen below 0.1% of their initial value.

(a) How much half-lives does this take? (Answer = 10 half-lives)

(b) Plutonium-239 is a by product of nuclear reactors. Its half-life is
24 000 years. How long does the plutonium-239 have to be stored as
nuclear waste before it is considered safe to handle? (Answer - 240 000
years)

[vedhamara]

Thanks for actually giving an explanation unlike my teacher

[notgarcian]

made it looked so simple, thanks for the help :)