Question

in an aquarium 2/5 of the fish are surgeonfish. of these three fourths are yellow tangs what fraction of all fish in the aquarium or yellow tangs

Answer 1

Let the total number of fish in the aquarium be x .

And out of them, 2/5 are surgeonfish , that is

$\frac{2x}{5}$

And out of 2/5 surgeonfish , 3/4 are yellowtangs, that is

$\frac{3}{4}* \frac{2x}{5} = \frac{6x}{20} = \frac{3x}{10}$

Required fraction is

$\frac{3x/10}{x} = \frac{3}{10}$