Question 631356
The tutor's head start is {{{ 7*3 = 21 }}} km
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Start a stopwatch when the recruit cyclist leaves.
They will now travel for the same amount of
time until they meet.
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Let {{{ d }}} = the distance the R.C. will travel
until she catches tutor
Tutor's equation:
(1) {{{ d - 21 = 7t }}}
R.C. equation:
(2) {{{ d = 17t }}}
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By substitution:
(1) {{{ 17t - 21 = 7t }}}
(1) {{{ 10t = 21 }}}
(1) {{{ t = 2.1 }}} hrs
{{{ .1*60 = 6 }}} min
The R.C. will overtake the Tutor in 2 hrs and 6 min
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check:
(1) {{{ d - 21 = 7t }}}
(1) {{{ d - 21 = 7*2.1 }}}
(1) {{{ d = 14.7 + 21 }}}
(1) {{{ d = 35.7 }}} km
and
(2) {{{ d = 17t }}}
(2) {{{ d = 17*2.1 }}}
(2) {{{ d = 35.7 }}} km
OK