Question

Determine how many days t will the two isotopes have the same activity

Answer 1

t = 1 ... one day

Explanation:

3 x
`10^(18)` *
`(.5)^(t)` = 6 x
`10^(18)` *
`(.5)^(2t)`

3 x
`10^(18)` =
`(.5)^(2t)` /
`(.5)^(t)`

6 x
`10^(18)`

1/2 =
`.5^(t)`

ln( 1/2) = t ln(
`.5` )

t = ln( .5)/ln(
`.5` )

t = 1