DS from 800score

The question stem says

m+n=250 and m>n ..

From this statement we can say that since m is greater than n, m has to be greater than 125 ..

.. Now, the question asked is, is (m-r)>(s-n)... which can also be interpreted as is a.) m+n>r+s or
is b.) m> r+s-n..

now let us look at the statements.. the first statement says
250>r+s ..

Now, the original question can be interpreted as, is m+n>r+s.... but m+n=250 so our question basically boils down to is 250>r+s and the first statement answers this question so the first statement is sufficient.

The second statement says m+r+s=375 but m=250-n, substituting this value of m we get r+s-n=125 ..

now again our original question can be interpreted as, is m>r+s-n but as we see r+s-n=125 so the question boils down to is m>125 and as already mentioned since m > n, m has to be greater than 125 ... so this statement is also sufficient.

So the answer is D .. hope that helps

Regards

That makes sense.. Good explanation gabriel.. OA is D