
Half life
At the beginning of an experiment, a scientist has 100 grams of radioactive goo. After 225 minutes, her sample has decayed to 12.5 grams.
1. What is the halflife of the goo in minutes?
2. Find a formula for G(t), the amount of goo remaining at time t. G(t) =
3. How many grams of goo will remain after 41 minutes?
I got 1. It is 75 minutes
how do you find a formula???

Re: Half life
$\displaystyle G(t) = G_0 \left(\frac{1}{2}\right)^\frac{t}{h}$
$\displaystyle G_0$ = amount at time $\displaystyle t = 0$
$\displaystyle h$ = halflife

Re: Half life
so that is the formula for number 2?

Re: Half life
100(1/2)^(t/75)
that's the forumla.
now i just plug in 41 minutes for t.