If a person walks at 15 km/hr instead of 10 km/hr, he would have walked 20 km more. The actual distance traveled by him is: Select the correct option.
A) 50 km
B) 56 km
C) 60 km
D) 40 km
E) 80 km

Rationale: "let the actual distance travelled be x km . x / 10 = ( x + 20 ) / 15 15 x = 10 x + 200 5 x = 200 x = 40 km . answer : d"
Answer: D