Question 1062938
Let {{{ s}}} = the speed of the boat in still water in km/hr
Let {{{ c }}} = the speed of the current in km/hr
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Equation for traveling upsteam
(1) {{{ 8 = ( s - c )*6 }}}
Equation for traveling downstream:
(2) {{{ 32 = ( s + c )*6 }}}
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(1) {{{ 8 = 6s - 6c }}}
(1) {{{ 3s - 3c = 4 }}}
and
(2) {{{ 32 = 6s + 6c }}}
(2) {{{ 3s + 3c = 16 }}}
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add (1) and (2)
(1) {{{ 3s - 3c = 4 }}}
(2) {{{ 3s + 3c = 16 }}}
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{{{ 6s = 20 }}}
{{{ s = 10/3 }}} km/hr
and
(1) {{{ 3s - 3c = 4 }}}
(1) {{{ 3*(10/3) - 3c = 4 }}}
(1) {{{ 10 - 3c = 4 }}}
(1) {{{ 3c = 6 }}}
(1) {{{ c = 2 }}} km/hr
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check answer
(1) {{{ 8 = ( s - c )*6 }}}
(1) {{{ 8 = ( 10/3 - 6/3 )*6 }}}
(1) {{{ 8 = (4/3)*6 }}}
(1) {{{ 8 = 8 }}}
and
(2) {{{ 32 = ( s + c )*6 }}}
(2) {{{ 32 = ( 10/3 + 6/3 )*6 }}}
(2) {{{ 32 = (16/3)*6 }}}
(2) {{{ 32 = 32 }}}
OK
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Is the 2nd part a different boat? Anyway, you
solve it the same way I just did. check the math.