A car completes a trip in 20 minutes. for the first half of the trip the speed of the car was 100km/h and the speed for the second half of the trip was 90km/h. How far did the car travel (in km) if the distance for the first part is the same as the second part
To find the total distance that the car traveled, you need to know the speeds of the car for each half of the trip and the time it took to complete the trip.
Let's start by calculating the time taken for each half of the trip.
Since the car completed the entire trip in 20 minutes, the time taken for each half would be half of that time, which is 10 minutes or 10/60 hours (since there are 60 minutes in an hour).
Next, we can use the formula Distance = Speed × Time to find the distance for each half of the trip.
For the first half of the trip, the speed was 100 km/h, and the time taken was 10/60 hours. Therefore, the distance covered in the first half of the trip is:
Distance 1 = Speed 1 × Time 1 = 100 km/h × 10/60 hours
Simplifying this equation, we get:
Distance 1 = 100 km/h × 1/6 hours = 100/6 km
Now, since the distance for the first part of the trip is the same as the distance for the second part, the total distance traveled by the car is twice the distance for the first half. Therefore, the total distance (D) covered by the car is:
D = 2 × Distance 1 = 2 × (100/6) km
Simplifying this equation gives:
D = 200/6 km
Thus, the car traveled approximately 33.33 kilometers.
Let the total distance be 2d. Then, since time = distance/speed,
d/100 + d/90 = 1/3