Answer:
$847
Step-by-step explanation:
25 bicycles
gray : black
6 : 9 (6+9=15)
25 divided by 15 = 1.666666667
x 9 (that's how many blacks)
= 15
there are 15 blacks
Answer:

Step-by-step explanation:
Given
Let the total probability be 1
Probability that Brian wins a raffle = n/n+2
Probability that Brian does not win a raffle = 1 - Probability that Brian wins a raffle
Probability that Brian does not win a raffle = 1 - (n/n+2)
Probability that Brian does not win a raffle = 
Probability that Brian does not win a raffle = 
Hence required fraction is