Solve for y help me out

The number of revolutions of two pulleys is inversely proportional to their diameters. if a 24-inch diameter pulley making 400 revolutions per minute is belted to an 8-inch diameter pulley, find the number of revolutions per minute of the smaller pulley.

Write the expression in complete factored form. 5n_(c - 3) - n(c - 3) =

I’m stuck on this equation, anyone got the answer?