Two cars 350 kilometers apart begin driving toward each othe

Two cars, 350 kilometers apart, begin driving toward each other on a long, straight highway. One car travels 100 kilometers per hour and the other 75 kilometers per hour. At the same time, a canary, starting on one car, flies back and forth between the two cars as they approach each other. If the canary flies 90 kilometers per hour and spends no time to turn around at each car, how far has it flown when the cars collide? The canary has flown kilometers.

Solution

RElative speed of cars is 100+75=175 km/h

Total distance to be travelled is 350 km

So, time taken =350/175=2 hours

SO distance travelled by canary =90*2=180 km