Data Sufficiency

In a two-story apartment complex, each apartment on the upper floor
rents for 75 percent as much as each apartment on the lower floor.
If the total monthly rent is $15,300 when rent is collected on all of
the apartments, what is the monthly rent on each apartment on the
lower floor?

(1) An apartment on the lower floor rents for $150 more per month than
an apartment on the upper floor.

(2) There are 6 more apartments on the upper floor than on the lower floor.

Is it A?

Lower = x
Upper = 0.75x

1 - 25% contributes to 150$ difference. So, 100% = 600. So, sufficient

2 - insufficient. (n+6)*0.75*x + nx = 15300. Can't solve for n and x.