Question 950277
Ralph's rate of painting is:
( 1 fence ) / ( 8 hrs )
{{{ 35 }}} min = {{{ 35/60 = 7/12 }}} hrs
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In {{{ 35 }}} min, Ralph paints:
{{{ ( 1/8 )* ( 7/12 ) = 7/96 }}} fraction of the fence
That means there is {{{ 1 - 7/96 = 89/96 }}}
of the fence left to paint
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Add their rates of painting to get rate painting together
Let {{{ t }}} = time in hrs for them to paint
the fence working together
{{{ 1/8 + 1/11 = (( 89/96 )) / t }}}
Multiply both sides by {{{ 11*96t }}}
{{{ 11*12t + 96t = 11*89 }}}
{{{ 132t + 96t = 979 }}}
{{{ 228t = 979 }}}
{{{ t = 979/228 }}} hrs
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Doesn't seem right if they mention "simplified"
I think my method is right, though -check the
math & get another opinion, too