Question

the ratio of the number of angelfish in the fish tank is 2:3 the numbers of angelfish in a fish tank is 1 fourth of the number of guppies

Answer 1

I will assume you meant to say:
number of angelfish : number of guppies = 2 : 3 or 2x : 3x

given:
2x = (1/4)(3x)
2x = (3/4)x

this makes no sense