Question

8.2. A thief steals a car at 1.30 p.m. and drives it off at 40 km/hr. The theft is discovered at 2 p.m. and the owner sets off in another car at 50 km/ hr. He will overtake the thief at (1) 5 p.m. (2) 4 p.m. (3) 4.30 p.m. (4) 6 p.m.

11th - 12th Class

Maths

Solution

164

5.0 (1 ratings)

Sol. (2) Distance covered by the thief in half an hour ( =frac{1}{2} times 40=20 mathrm{km} ) Relative speed of car owner ( =50-40=10 mathrm{km} ) ( therefore ) Required time ( =frac{text { Difference of distance }}{text { Relative speed }} ) ( =frac{20}{10}=2 ) hours i.e. at ( 4 mathrm{p} cdot mathrm{m} )