Question 1101542
Let {{{ V }}} = the total volume of tank B
{{{ (1/4)*V }}} = the total volume of tank A
Let {{{ v[A] }}} = volume of water initially in tank A
Let {{{ v[B] }}} = volume of water initially in tank B
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{{{ v[A] / v[B] = 4/3 }}}
{{{ v[B] = (3/4)*v[A] }}}
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{{{ v[A] + .8 = (1/4)*V }}}
{{{ v[A] + .8 = 2*v[B] }}}
{{{ v[A] + .8 = 2*(3/4)*v[A] }}}
{{{ v[A] + .8 = (3/2)*v[A] }}}
{{{ (1/2)*v[A] = .8 }}}
{{{ v[A] = 1.6 }}}
and
{{{ v[B] = (3/4)*v[A] }}}
{{{ v[B] = (3/4)*1.6 }}}
{{{ v[B] = 1.2 }}}
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{{{ v[A] + .8 = (1/4)*V }}}
{{{ 1.6 + .8 = (1/4)*V }}}
{{{ 2.4 = (1/4)*V }}}
{{{ V = 9.6 }}}
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{{{ V - v[B] = 9.6 - 1.2 }}}
{{{ V - v[B] = 8.4 }}}
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8.4 liters of water is needed
to fill B to the brim
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Definitely get a 2nd opinion unless
you don't need to
( hope that big V and little v do not
confuse you )