Question 1109560
Question should be  How long will it take for SALLY to catch up with MARK if MARK had a two hour head start?


<pre>
                  SPEED      TIME      DISTANCE
SALLY              65        d/65         d
MARK               50        d/50         d
DIFFERENCE                    2
</pre>

When did Sally and Mark reach the same distance d?


{{{d/50-d/65=2}}}

-

{{{(d/50)(13/13)-(d/65)(10/10)=2}}}

{{{13d/650-10d/650=2}}}

{{{3d/650=2}}}

{{{d=2(650/3)}}}

{{{highlight(d=433&1/3)}}}, miles when Sally catches up.


Sally traveled for {{{6&2/3}}} hours
and
Mark for {{{8&2/3}}} hours.