GPREP1, Pets

IMO D.
First statement is straight forward.. so A is sufficient
second statement

its says there are 20 more dogs than birds

let the total number pets be X
we know birds = X/5
dogs = x/5+20......................................1
but the question stem says dogs are 1/3 of total pets
hence its X/3.........................................2

equate 1 and 2

x/5+20 = x/3
solve it to get total numbers of pets as 150.

hence 2 is sufficient.

hence D

It just says dogs are 20 more than birds.

if total is x then according to q : Dogs=x/3 and Birds=x/5

so x/3=x/5+20, then x is achievable...and so on..


Amit

Thanks guys!

Not that it matters for this specific problem, but why is 20 added to the (X/5) side? It says there are 20 more dogs (which is X/3) then birds(X/5), so shouldn't 20 be added to the side w/ dogs?

the side of the birds because


if I have x apples, and you have y apples, and I have 10 more apples than you do, it means that you should add 10 apples to y to get x.

or, if you substract x-y=20, x=y+20

Get it?

Yes, thanks Santa_Dem!