First you take 15 and divide it by 5. That leaves you with 3. You also need to decide the x’s so you subtract the exponents (2-3=-1)
so you now have (y^10z^7)/(y^4z^10)3x^-1
Next we will divide the y’s.
Again, subtract the exponents (10-4=6) to get y^6
Now we have (3x^-1)(y^6) (z^7/z^10)
Last is z, we subtract the exponents again (7-10=-3) and get z^-3
Our answer is (3x^-1)(y^6)(z^-3)