Globular clusters and distance to earth?? please help!?

Question

I observe two different globular clusters and make HR diagrams for the stars in each. In globular cluster A, the apparent brightness of the G Main Sequence stars is 100 times fainter than the apparent brightness of the G Main Sequence stars in globular cluster B.

Which cluster is closer to the Earth, A or B?

How much closer is it to us?

Answer 1

B is closer to the Earth because its main sequence stars are 100 times brighter.  B is 10 times closer to the Earth because of the inverse square law.