Question 935602
{{{ d = r*t }}}
{{{ d }}} is in miles
{{{ r }}} is in mi/hr
{{{ t }}} is in hours
(1) {{{ d = r*2 }}}
(2) {{{ d = ( r - 5 )*( 2 + 12/60 ) }}}
(2) {{{ d = ( r - 5 )*( 2 + 1/5 ) }}}
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Substitute (1) into (2)
(2) {{{ 2r = ( r - 5 )*2.2 }}}
(2) {{{ 2r = 2.2r - 11 }}}
(2) {{{ .2r = 11 }}}
(2) {{{ r = 55 }}}
and
(1) {{{ d = r*2 }}}
(1) {{{ d =55*2 }}}
(1) {{{ d = 110 }}}
It is 110 mi from London to Birmingham
The train's average speed is 55 mi/hr