A researcher wants to conduct a genetic study using 10 randomly-selected volunteers. He has a volunteer pool of 20, composed of 10 males and 10 females. What is the probability that the randomly-selected group will be all male OR all female?
A. 1/184,756
B. 1/92,378
C. 5/138,567
D. 1/138,567

Question

A researcher wants to conduct a genetic study using 10 randomly-selected volunteers. He has a volunteer pool of 20, composed of 10 males and 10 females. What is the probability that the randomly-selected group will be all male OR all female?
	A.	1/184,756
	B.	1/92,378
	C.	5/138,567
	D.	1/138,567

anonymous · Answer

all male 
$$\frac{1}{\binom{20}{10}}$$ same for all female so answer is 
$$\frac{2}{\binom{20}{10}}$$