A person takes one hour more to cover a certain distance walking at a speed of 2 km/hour compared to walking at 3 km/hour. The distance is
6 km
Let's figure out the distance the person traveled using the information about their speeds and the difference in time taken.
The relationship between distance, speed, and time is a fundamental concept in motion problems. It is given by the formula:
\( \text{Distance} = \text{Speed} \times \text{Time} \)
From this formula, we can also express time as:
\( \text{Time} = \frac{\text{Distance}}{\text{Speed}} \)
Let the unknown distance be \(d\) kilometers.
We are given two different speeds at which the person walks:
Let \(T_1\) be the time taken to cover the distance \(d\) at Speed 1, and \(T_2\) be the time taken to cover the same distance \(d\) at Speed 2.
Using the formula \( \text{Time} = \frac{\text{Distance}}{\text{Speed}} \), we can write the time taken for each speed:
The problem states that the person takes one hour more to cover the distance walking at 2 km/hour compared to walking at 3 km/hour. This means the difference between the two times is 1 hour.
So, we can write the equation:
\( T_1 - T_2 = 1 \)
Substitute the expressions for \(T_1\) and \(T_2\) we found earlier:
\( \frac{d}{2} - \frac{d}{3} = 1 \)
Now, we need to solve this equation to find the value of \(d\).
To subtract the fractions on the left side, we need a common denominator. The least common multiple of 2 and 3 is 6.
Multiply the first term by \( \frac{3}{3} \) and the second term by \( \frac{2}{2} \):
\( \frac{d}{2} \times \frac{3}{3} - \frac{d}{3} \times \frac{2}{2} = 1 \)
\( \frac{3d}{6} - \frac{2d}{6} = 1 \)
Combine the fractions on the left side:
\( \frac{3d - 2d}{6} = 1 \)
\( \frac{d}{6} = 1 \)
To isolate \(d\), multiply both sides of the equation by 6:
\( d = 1 \times 6 \)
\( d = 6 \)
The distance covered is 6 kilometers.
Rishi travels 198 km at 66 km/hr, the next 584 km at 73 km/hr and the next 656 km at 82 km/hr. What is his average speed (in km/hr) for the whole journey? (Round off your answer to two decimal places)