Question 998977
With replacement, multiply the probabilities.
type)O A B AB
Rh+ 95 97 38 17 =247
Rh- 25 16 8 4 ;;;;=53
 ;;;;120/113/46/21=300
A+ is 97/300
With replacement the probability of 2 is (97/300)^2=0.1045
Without replacement, the probability is (97/300)*(96/299)=0.1038
The numerator and the denominator both decrease 1, and because of the relatively large sample, the change in probability is not much.  It is lower, and it should be with one less A+ to choose from.