Question 197074
There are 385 surfers in Surf City. Two thirds of the boys are surfers
 and one-twelfth of the girls are surfers.
 If there are two girls for every boy, then how many boys and how many
 girls are there in Surf City?
:
You got a good start
{{{1/12}}}x + {{{2/3}}}y = 385
Get rid of those annoying fractions, multiply by 12
x + 4(2y) = 12(385)
x + 8y = 4620
:
Then it says,"there are two girls for every boy" therefore we can say:
x = 2y
:
substitute 2y for x:
2y + 8y = 4620
10y = 4620
y = {{{4620/10}}}
y = 462 boys, obviously then, 924 girls
:
:
Check solution in original equation:
{{{1/12}}}x + {{{2/3}}}y = 385
{{{1/12}}}(924) + {{{2/3}}}(462) = 
77 + 308 = 385; confirms our solution
;
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