check the correctness of the relation:

density = 3g/4 pi r G , where the letters have their usual meanings.

we have

ρ = (3g / 4.r.G)

here,

the dimensions of LHS is

= [ML^-3]

the dimensions of RHS will be

= [LT^-2]  / { [L] . [M^-1L³T^-2] }

= [ML^-3]

so,

as dimensions of LHS = dimensions of RHS

the above equation is dimensionally correct.