You arrive at your school 5 minutes late if you walk with a speed of 4 km/hr, but you arrive 10 minutes before the scheduled time if you walk with a speed of 5 km/hr. The distance of your school from your house is :
Q. You arrive at your school 5 minutes late if you walk with a speed of 4 km/hr, but you arrive 10 minutes before the scheduled time if you walk with a speed of 5 km/hr. The distance of your school from your house is :
Answer: 5 km
Notes: If the required distance be x km, then $latex \frac{x}{4} - \frac{x}{5} = \frac{10+5}{60}&s=1$ $latex => \frac{5x - 4x}{20} = \frac{1}{4}&s=1$ $latex => \frac{x}{20} = \frac{1}{4}&s=1$ $latex => x = \frac{1}{4}\times 20 = 5\ km&s=1$ Hence option [C] is correct answer.