Solution
For this case we have the following function :
Color Number of times
Blue 164
Green 86
Red 104
Yellow 146
The total of trials are:
164+ 86+ 104+146= 500
Then the probability of being red is given by:
104/500= 0.208
And then if we convert to % we got:
0.208*100 = 20.8
and then the answer is:
B. 21%