Qu: G:A=?
A+S+G=Total

(1) There are 200 fish in the aquarium
We know Total=200 , no information on distribution among A, S and G. NOT SUFFICIENT

(2) 45 percent of the fish are swordtails, and there are twice as many swordtails as there are angelfish.
45%T =S
S=2A
so we know G+A combine to 55% and A is \(45/2 %\) so G will be \(100-45-22.5\)
we cannot find individual number of fish of each type but we can surely find G:A.

Option B : Sufficient .

Let A,S & G are # of fishes in the tank; # of G/# of A =?

1. Total = 200, no idea about of G & A, insufficient
2. Let total is x, so s=0.45x, a= 0.45x/2 and G= x-3*0.45x/2; so #of G/# of A can be determined by given values. Sufficient

Hence answer is B

Given: A certain aquarium holds three types of fish: angelfish, swordtails, and guppies.

Target question: What is the ratio of the number of guppies to the number of angelfish?

Statement 1: There are 200 fish in the aquarium.
Since we are not giving any information about the number of each type of fish, statement 1 is NOT SUFFICIENT

Statement 2: 45 percent of the fish are swordtails, and there are twice as many swordtails as there are angelfish.
There are twice as many swordtails as there are angelfish. 45% ÷ 2 = 22.5%
So, 45% are swordtails and 22.5% are angelfish.

Since all three percentages must add to 100%, we can conclude that the remaining 32.5% are guppies.
We can write: swordtails : angelfish : guppies = 45 : 22.5 : 32.5
The answer to the target question is the ratio of guppies to angelfish = 32.5 : 22.5
Since we can answer the target question with certainty, statement 2 is SUFFICIENT

Answer: B

Cheers,
Brent
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