Solution
Given
Red = 5
Green = 8
Blue = 4
Total = 5 +8 + 4 = 17
Probability of either red or green = prob. of red + prob of green
The use of 'OR' in probabilities simply means addition of the probabilities
P( red ) = number of red tokens / Total number of tokens
P(red) = 5 /17
P(green) = 8/17
P(red or green ) is obtained as shown below
[tex]\frac{5}{17}+\frac{8}{17}=\frac{13}{17}[/tex]The final answer is
[tex]\frac{13}{17}[/tex]