Answer:
a. 1/25
b. 25/1
Explanation:
There are 2 black 7s in a deck (7 of spades and 7 of clubs). So there are 50 cards that are not black 7s.
The odds in favor of drawing a black 7 is therefore 2/50 = 1/25.
The odds against drawing a black 7 is therefore 50/2 = 25/1.