So the standard deviation of the numbers in set T,is 3 times the standard deviation of the numbers in set S,9 . C
In bag X, there are 5 green disks among a total of 7 + 5 = 12 disks. The probability of choosing
a green disk from bag X is . In bag Y, there are 15 green disks among a total of 15 + 5 = 20
disks. The probability of choosing a green disk from bag Y is , or . Since the selections of
the disks from the bags are independent, the probability that both disks selected are green
is