Designing a Formula? **QUESTION:** > The half-life of a drug is the time it takes for a dose to reduce to half its initial amount. A doctor prescribes a 4mg sleeping pill with a half-life of 24 hours. > > Write down a formula connecting the mass, m, of drug remaining with its half-life, t. * * * I know that is halves every $24$ hours however I'm not sure where to start except from.... $m = t$ Thank you.

If the quantity reduce to $1/2=2^{-1}$ in $24 $ hours than the quantity $m$ at $ h$ hours is:

$$ m=m_02^{-(\frac{h}{24})} $$ where $m_0$ is the initial dose.