Question 1124458
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<U>Short solution and the answer</U>


<pre>
Time = {{{(60*1.2)/(70-60)}}} = 7.2 hours = 7 hours and 12 minutes.     // Option E).
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<U>Explanation</U>


<pre>
At the moment John starts, Clara is 60*1.2 miles ahead.


Their relative speed is  70-60 = 10 miles per hour.

It is the rate of decreasing the distance between them.


Therefore,  the ratio  {{{(60*1.2)/(70-60)}}}  is the time when John will catch up Clara.
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