Question 369022
{{{F=(Gm[1]m[2])/r^2}}}
{{{r^2=(Gm[1]m[2])/F}}}
{{{highlight(m[2]=(r^2F)/(Gm[1]))}}}
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This is Newton's law of universal gravitation (although you're missing a negative sign).
Two bodies are attracted to each other proportional to the product of their masses and inversely proportional to the square of the distance between them.