A `""^118Cd` radio nuclide goes through the transformation chain.
`""^118Cd underset(30min) rarr^(118)In underset(45min)rarr^(118)Sn ("stable")`
The half-lives are written below the respective arrows. At time `t=0` only Cd was present. Find the fraction of nuclei transformed into stable over `60` minutes.

A radionuclide A_(1) goes through the transformation chain A_(1) rarr A_(2) rarr A_(3) (stable) with respective decay constants lambda_(1) and lambda(2) . Assuming that at the initial moment the preparation contained only the radionuclide A_(1) equal in quantity to N_(10) nuclei, find the equation describing accumulation of the stable isotope A_(3) .