Question 951384
How much of the fence does Ralph paint in {{{ 45 }}} min ?
{{{ 45/60 = 3/4 }}} hrs
Ralph's rate of painting is:
( 1 fence ) / ( 14 hrs )
----------------------
( Ralph's rate ) x ( time spent painting ) = ( fraction of fence painted )
{{{ ( 1/14 )*( 3/4 ) = 3/56 }}}
That means there is {{{ 1 - 3/56 = 53/56 }}} of the fence left to paint
----------------------
Add their rates of working to get rate working together
L:et {{{ t }}} = their time in hrs to paint the remaining
{{{ 53/56 }}} of the fence
----------------------
{{{ 1/14 + 1/17 = (( 53/56 )) / t }}}
Multiply both sides by {{{ 17*56t }}}
{{{ 4*17t + 56t = 17*53 }}}
{{{ 68t + 56t = 901 }}}
{{{ 124t = 901 }}}
{{{ t = 901/124 }}} hrs
Strange result. Get another opinion. I may have
answered this twice. If so, sorry. I really think
my method is OK, though