Question 649267
Let {{{ t }}} = time in hrs for Jim's hose alone to fill pool
{{{ .8t }}} = time in hrs for Bob's hose alone to fill pool
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Add their rates of filling to get rate filling together
{{{ 1/t + 1/(.8t) = 1/18 }}}
Multiply both sides by {{{ .8*t*18 }}}
{{{ .8*18 + 18 = .8t }}}
{{{ .8t = 18 + 14.4 }}}
{{{ .8t = 32.4 }}}
{{{ t = 40.5 }}}
40.5 = time in hrs for Jim's hose alone to fill pool
32.4 = time in hrs for Bob's hose alone to fill pool
check:
{{{ 1/t + 1/(.8t) = 1/18 }}}
{{{ 1/40.5 + 1/32.4 = 1/18 }}}
{{{ .0247 + .03086 = .05555 }}}
{{{ .05556 = .05555 }}}
OK