logistic equation $\displaystyle \frac {dP}{dt} = rP \left( 1 - \frac PK \right)$

world population in 1990 was about 5.3 billion, with intrinsic growth rate r of 0.0038 per year, assume a carrying capacity K = 100 billion for the world population

how do i use that to write down the logistic IVP with t=0 in 1990???