Question

Question 9:

A father and his son start at a point A with speeds of 12 km/h and 18 km/h respectively and reach another point B. If his son starts 60 min after his father at A and reaches B, 60 min before his father, what is the distance between A and B? एक पिता और उसका बेटा क्रमशः 12 किमी प्रति घंटे और 18 किमी प्रति घंटे की गति के साथ एक बिंदु A पर शुरू करते हैं और दूसरे बिंदु B पर पहुंचते हैं। यदि उसका बेटा A पर अपने पिता के बाद 60 मिनट से शुरू होता है और अपने पिता से 60 मिनट पहले B तक पहुंचता है, तो दूरी क्या है A और B के बीच?

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Answer 1

Explanation:

Let the distance between A and B is x km.

Time taken by father to cover x km at a speed of 12 Km/hr = x12hoursx12hours

And time taken by son to over x km at a speed of 18 Km/hr = x18hoursx18hours

According to question,

= x12−x18=60+6060x12−x18=60+6060

= > 3x−2x36=23x−2x36=2

= > x=2×36x=2×36

= 72 km