Once you attempt the question then PrepInsta explanation will be displayed.
From the condition we know that the old man passes 1/30 of the way in
1 minute. So in 5 minutes, he'll pass 1/6
So we could think of the problem like this. They both start at the same time,
but the old man need to pass 5/6 of the way, while the young man
should walk whole way. We aleady know that the old man pass
1/30 of the way in a minute, while the young man pass 1/20of the
way in a minute. So we need to find solution to the following equation:
1−(1/20)t=5/6−(1/30)t
1−t/20=5/6−t/30
1−5/6=(1/20−1/30)t
1/6=1/60t
⟹t=10
So theyll meet 10 minutes after the young man starts his journey, i.e in
10:15am.
Video solution:
src="https://www.youtube.com/embed/i_9dHx38bZY"
frameborder="0" allowfullscreen="" style="position: absolute; top:0; left: 0">
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