Question

Mahindra starts a Journey for his office, which is in the north east at his home. An hour After starting meets with a minor accident. He takes one hour in resuming his journey. After that he proceeds at 5/6th of his former speed and arrives as the office 1 hour 36 minutes late than the scheduled time. Had the accident occurred 80 kms further from the actual place of accident, he would have arrived 1 hour 20 minutes beyond the scheduled time. What is the distance between his office and his home?

• A. 180 km
• B. 240 km
• C. 250 km
• D. 300 km

Answer 1

The correct option is B 240 km

Note that he rested for one hour before he began his journey again.
In first case,
Speed decreases by $\frac{1}{6}$ times. So, time increases by 1/5 times
Hence, $\frac{t}{5}$ = 36 min => t = 180 min with original speed.
In second case, consider that 80 km which had different speed in both the cases.
Speed decreases by $\frac{1}{6}$ times. So, time increases by 1/5 times
Hence, $\frac{t}{5}$ = 16 min => t = 80 min with original speed, means 80 km in 80 min.
Hence, original speed = 60 kmph = 1 kmph
Total scheduled journey time = 180 + 60 min = 240 min
$\therefore$ Required distance = $240\times 1=240km.$


Alternative Approach:
$\Rightarrow$ actual time required for (x - 80) km = $5\times 20$ = 100 min
It means he can move = x - (x - 80) = 80 km in
(180-80) = 80 min
It means his actual speed = 60 km/h
Thus, the total distance from his home to his office
$60\times 1+60\times 3=240$ km