Stratified Random Sampling
It is 0.02
1/26
24 - 1
a black one
Assuming the choices are made randomly and that the chosen people are not returned to the class, the probability is 77/690 = 0.1116 approx.
The probability is 0.4231, approx.
It is approx 78.8%
Empirical
1 in 13
It is 0.02
It is 3/8.
1/26
stratified sample
2/4
0.7881 approx.
50%
3/10 or 0.3