InterviewSolution
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InterviewSolution
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2 Workers, One Old And One Young, Live Together And Work At The Same Office. The Old Man Takes 30 Mins Whereas The Young Man Takes Only 20 Mins To Reach The Office. When Will The Young Man Catch Up The Old Man, If The Old Man Starts At 10.00am And The Young Man Starts At 10.05am? |
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Answer» LET the SPEED of old man be: X m/min and that of young man be: y m/min If the distance of the office be D METER, then A/c: D = 30x = 20y or y = 1.5x Let young man catches old man after ‘t’ mins. So distance travelled by young man is ‘t’min = ty = 1.5tx And distance travelled by old man in ‘t+5’min = (t+5) x = tx + 5x THEREFORE, A/c: 1.5tx = tx + 5x or 0.5tx = 5x or t = 10min So young man catches the old man at 10:05 AM + 10min i.e 10:15 min Alternate method Old man takes 30 min i.e. he travels from 10:00 AM to 10:30 AM Young man takes 20 min i.e. he travels from 10:05 AM to 10:25 AM From symmetry; they will meet in mid-way of the journey at 10:15 AM. Let the speed of old man be: x m/min and that of young man be: y m/min If the distance of the office be D meter, then A/c: D = 30x = 20y or y = 1.5x Let young man catches old man after ‘t’ mins. So distance travelled by young man is ‘t’min = ty = 1.5tx And distance travelled by old man in ‘t+5’min = (t+5) x = tx + 5x Therefore, A/c: 1.5tx = tx + 5x or 0.5tx = 5x or t = 10min So young man catches the old man at 10:05 AM + 10min i.e 10:15 min Alternate method Old man takes 30 min i.e. he travels from 10:00 AM to 10:30 AM Young man takes 20 min i.e. he travels from 10:05 AM to 10:25 AM From symmetry; they will meet in mid-way of the journey at 10:15 AM. |
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