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Mark left town P for town Q at 10am, travelling at a uniform speed of 75km/h.
Jane left town P for town Q an hour after Mark, travelling at 120km/h.
She passed Mark after travelling 2/5 of the journey. she reached town Q at 4 pm.
How far was Jane from town Q when she passed Mark?
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When Jane left town P for town Q at 11 am, Mark was 75 km ahead.
The difference of their speeds is 120 - 75 = 45 km/h.
Hence, Jane passed Mark in = hours, counting from 11 am.
During this time, hours, Jane covered the distance of = 40*5 = 200 km.
This distance, 200 km, is of the distance from P to Q, according to the problem.
Hence, the whole distance from P to Q is = 500 km.
From the other side, Jane traveled 5 hours (from 11 am to 4 pm) at the speed of 120 km/h -
hence, she traveled 5*120 = 600 km.
Thus we obtained two different values, 500 km and 600 km, for the distance from P to Q.
It tells us that the different parts of the problem are not consistent.
Thus, the problem is SELF-CONTRADICTORY, is posed INCORRECTLY and MAKES NO sense.
ANSWER. As presented in the post, the problem is SELF-CONTRADICTORY,
is posed INCORRECTLY and MAKES NO sense.
The problem in the post is composed in absolutely illiterate way.
All the accusations should be addressed to the problem's creator.