Question 875440
Add their rates of cleaning
Trey's rate:
( 1 house ) / ( 6 hrs )
Matt's rate:
( 1 house ) / ( 8 hrs ) 
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Let {{{ t }}} = the time in hrs for
them to clean the house together
{{{ 1/6 + 1/8 = 1/t }}}
Multiply both sides by {{{ 24t }}}
{{{ 4t + 3t = 24 }}}
{{{ 7t = 24 }}}
{{{ t = 3.4285 }}}
They can clean the house in 3.4285 hrs
working together