Question 839267
How far did Mr Strong get from 9:40 to 10:10 ?
The time difference is: {{{ .5 }}} hrs
{{{ d[1] = 60*.5 }}}
{{{ d[1] = 30 }}} km
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Let {{{ d }}} = distance Mr Swift travels until
he catches up with Mr Strong
Let {{{ s }}} = Mr Swift's average speed
Start counting time when Mr Swift leaves
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Mr Swift's equation:
(1) {{{ d = s*3 }}}
Mr Strong's equation:
(2) {{{ d - 30 = 60*3 }}}
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(2) {{{ d = 180 + 30 }}}
(2) {{{ d = 210 }}}
and
(1) {{{ d = s*3 }}}
(1) {{{ 210 = s*3 }}}
(1) {{{ s = 70 }}}
Mr Swift's average speed is 70 km/hr