Planet X has nine times the diameter and three times the mass of the earth.

Planet X has nine times the diameter and
three times the mass of the earth.
What is the ratio gX : ge of gravitational
acceleration at the surface of planet X to the
gravitational acceleration at the surface of the Earth?

-Shay.

Why does this question look so familiar?

g2/g1 = m2/m1 * (r1/r2) ^2
= 3 *(1/9)^2
= 3/27
= 1/9 of the gravitation here on earth.