Question 562302
Candy's rate is ( all the papers ) / ( 70 min )
Tim's rate is ( all the papers ) / ( 80 min )
Call "all the papers" 1 job
Add their rates to get rate working together
Let {{{ t }}} = minute to do 1 job working together
{{{ 1/70 + 1/80 = 1/t }}}
Multiply both sides by {{{ 560t }}}
{{{ 8t + 7t = 560 }}}
{{{ 15t = 560 }}}
{{{ t = 37.333 }}} min
{{{ .333*60 = 20 }}}
It takes them 37 min and 20 sec working together