L varies directly as the cube of M and inversely as the square root of n. If L =108 when m=3 and n= 4. Find N when L is 4000 and M is 10

Pls help me with this

L = kM^3/√N

that means L√N/M^3 = k, which is constant
so you want N such that
4000√N/1000 = 108√4/3^3
√N = 108*2/27 * 1000/4000 = 2
N = 4
makes sense, since 108/27 = 4000/1000
They could have chosen a better set of values, I think