The table shows, for a boat over five days (Monday to Friday), the distance travelled upstream (km), speed of boat (km/h), speed of stream (km/h) and total time (hours). Dashes are missing and to be calculated. Distance upstream = distance downstream; total time = downstream time + upstream time.
| Day | Distance Upstream (km) | Speed of Boat (km/h) | Speed of Stream (km/h) | Total Time (hours) |
|---|---|---|---|---|
| Monday | 320 | — | 4 | — |
| Tuesday | — | — | — | 75 |
| Wednesday | 270 | — | 6 | — |
| Thursday | — | 11 | 7 | — |
| Friday | 324 | — | — | 72 |
On Tuesday, if the difference between the time taken by the boat to go upstream and downstream is 45 hours and the downstream speed is 24 km/hour, then what is the total distance covered by the boat to go upstream and downstream?
The total distance covered upstream and downstream on Tuesday is 720 km.
Let the one way distance be x, downstream speed 24 km/h and upstream speed y km/h.
The time difference gives x over y minus x over 24 equals 45.
The total time gives x over y plus x over 24 equals 75.
Adding and subtracting these gives x equals 360 and y equals 6.
So each way is 360 km.
The total distance is 360 plus 360, which is 720 km.
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