Case 1: If the letter z is distinctly different
If we have the letter z which is distinctly different than the other "z", then we have five letters in the word F U Z Z Y and the number of arrangements would be = 5*4*3*2*1 =5! = 120 different arrangements
Case 2: If the letter Z is interchangeable
If the letter "Z" is interchangeable with the other "z" then we have 2 letters which cancel out each other that would be represented by 2*1 = 2! = 2
So, the number of arrangements in this case would be 5!/2! = 5*4*3*2*1/2*1 = 60 arrangements