A) prob (4reds) = (7/12)(6/11)(5/10)(4/9) = 7/99
or
Prob = C(7,4)/C(12,4) = 35/495 = 7/99
B) could be GGGG, GGGR
Prob = C(5,4)/C(12,4) + C(5,3)*C(7,1)/C(12,4
= 5/495 + 70/495 = 75/495 = 5/33
C) can't have all red or all green
prob = 1 - (all red + all green)
number of all green = C(5,4) = 5
so prob = 1 - (7/99 + 5/495) = 91/99
D) both are labelled 5
prob = C(2,2)*C(10,2)/C(10,4) = 45/495 = 1/11