Question 839140
Let {{{ r[1] }}} = the rate for the faster pipe
Let {{{ r[2] }}} = the rate for the slower pipe
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The rate of emptying the tank with both pipes
turned on is:
( 1 tank emptied ) / ( 10 hrs )
I can say:
{{{ r[2] - r[1] = -1/10 }}} ( emptying is a negative rate )
{{{ r[1] = 5*r[2] }}}
{{{ r[2] - 5*r[2] = -1/10 }}}
{{{ -4*r[2] = -1/10 }}}
{{{ r[2] = 1/40 }}}
The slower pipe takes 40 days to fill an empty tank
check:
{{{ r[2] - r[1] = -1/10 }}}
{{{ 1/40 - 5*(1/40) = -1/10 }}}
{{{ -4/40 = -1/10 }}}
{{{ -1/10 = -1/10 }}}
OK