3 + 4 +2 = 9 total marbles
If you pick a red one first and don't replace it that leaves a total of 8 marbles left
there are 4 blue marbles
so probability = 4/8, reduces to 1/2 probability of picking a blue marble
Answer:
c
Step-by-step explanation:
18/25= 21/x
18x=525
525/18 = 29.16
29.4
I'm thinking it's 42. Did you notice that there is a pattern?