Final answer:
To reach on time, the man should ride at a speed of approximately 46 km per hour, which is closest to 48 km per hour, to cover the distance of 50 km in 1 hour and 5 minutes.
Step-by-step explanation:
If a man rides a distance of 50 km at a speed of 50 km per hour, then he reaches 5 minutes early. To find out at what speed the man should ride to reach his destination on time, we need to calculate the time it would take to travel 50 km at the original on-time speed and then find the corresponding speed that will account for the 5 minutes added back.
First, let's find out the time taken to cover 50 km at a speed of 50 km/h:
Time = Distance / Speed = 50 km / 50 km/h = 1 hour
Since he is 5 minutes early, the correct time to cover the distance is 1 hour and 5 minutes, which is equal to 1 hour + 5/60 hours = 1.08333 hours.
To find the speed required to cover 50 km in 1.08333 hours, we use the formula:
Speed = Distance / Time = 50 km / 1.08333 hours ≈ 46.15 km/h
Therefore, the man should ride at a speed of approximately 46 km per hour to reach his destination on time. Which is closest to option (a) 48 km per hour.