Afish tank contains 14 goldfish 26 guppies. if you randomly select 2 fish what is the probility that they both are gold fish?
a.1/20
b. 1/26
c. 91/780
d. 1/384

The probability of selecting 2 goldfish from a fish tank is 91/780.

The probability of getting a goldfish from a first try is 14/40 because the total number of goldfish is 14 over the total number of fishes in the fish tank which is 40.
The probability of getting a goldfish on the second try is 13/39 because there are only 13 goldfish left over 39 total number of fishes left in the tank. 
Then,
P(selecting 2 goldfish) = (14/40)(13/39) = 182/1560 = 91/780