Question 604100
Let {{{ a }}} = number of adults in the zoo
{{{ 187 - a }}} = number of children in the zoo
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{{{ 7/4 = a/( 187-a ) }}}
Multiply both sides by {{{ 4*( 187 - a ) }}}
{{{ 7*( 187 - a ) = 4a }}}
{{{ 1309 - 7a = 4a }}}
{{{ 11a = 1309 }}}
{{{ a = 119 }}}
{{{ 187 - a = 187 - 119 }}}
{{{ 187 - a = 68 }}}
There are 68 children in the zoo
check answer:
{{{ 7/4 = 119/68 }}}
{{{ 7*68 = 119*4 }}}
{{{ 476 = 476 }}}
OK