Question 1135013
Let {{{ d }}} = distance between towns in km
Let {{{ t }}} = time to go from A to B in hrs
{{{ t + 3 }}} = time to go from B to A in hrs
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Going from A to B
(1) {{{ d = 55t }}}
Going from B to A:
(2) {{{ d = 40*( t + 3 ) }}}
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Plug (1) into (2)
(2) {{{ 55t = 40t + 120 }}}
(2) {{{ 15t = 120 }}}
(2) {{{ t = 8 }}}
It took 8 hrs to go from A to B
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check:
(1) {{{ d = 55*8 }}}
(1) {{{ d = 440 }}} km
and
(2) {{{ d = 40*11 }}}
(2) {{{ d = 440 }}} km
OK