Question 102960
assume there are {{{x}}} boys and {{{y}}} girls

{{{(2/3)x + (1/12)y = 385}}}
where {{{(2/3)x}}} represents the number of boy surfers, and {{{(1/12)y}}} represents the number of girl surfers
and 

{{{2x = y}}}  (two girls for every boy)

then:

{{{(2/3)x + (1/12)(2x) = 385}}}
{{{2x/3 + 2x/12 = 385}}}
{{{8x/12 + 2x/12 = 385}}}
{{{10x/12 = 385}}}
{{{10x = 4620}}}
{{{x = 462}}}...number of boys
{{{y = 2*462 = 924}}}...number of girls