Question 1157001
Jaun's rate of working is:
{{{ 2/4 = 1/2 }}} jobs/days
In 6 days he can do:
{{{ ( 1/2)*6 = 3 }}} jobs
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{{{ 107 - 3 = 104 }}} jobs left to be done
Let {{{ t }}} = time in days to do
{{{ 104 }}} jobs working together
Add their rates working together:
{{{ 1/2 + 4/5 = 104/ t }}}
Multiply both sides by {{{ 10t }}}
{{{ 5t + 8t = 1040 }}}
{{{ 13t = 1040 }}}
{{{ t = 80 }}}
It will take them 80 days working together to finish
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check:
{{{ 1/2 + 4/5 = 104 / t }}}
{{{ .5 + .8 = 104/80 }}}
{{{ 1.3 = 1.3 }}}
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check my math and get a 2nd opinion if needed