Fermium252 decays in 10 minutes to 761 of its original mass

Fermium-252 decays in 10 minutes to 76.1% of its original mass. Find the half-life of fermium-252.

Let the initial amount be 1

Therefore after 10 minutes Ferium-252 decays to .761

A=A₀2^-(t/h)

A₀ is the initial amount

h is the half life

.761=1 2^-^(10/h)

Taking log both sides we get

log .761= (-10/h)log 2

-10/h= log.761/log 2

h= 25.4 minutes