Note that thermally generated electrons `(n_(i) ~10^(16) m^(–3))` are negligibly small as compared to those produced by doping.
Therefore, `n_(e)approxN_(D)`.
Since `n_(e)n_(h) = n_(i)^(2)`, The number of holes
`n_(h) = (2.25 × 10^(32))//(5 ×10^(22))
~ 4.5 × 10^(9) m^(–3)`