If a person walks at 14 km/hr instead of 10 km/hr, he would have walked 20 km more. The actual distance travelled by him is :  Choose the most appropriate option
A) 52 km	B) 62 km	C) 55 km	D) 50 km	E) None
Sol.   Let the actual distance travelled be x km. Then,   x/10 = (x+20)/14   ⇔ 14x = 10x + 200   ⇔ 4x = 200   ⇔ x = 50 km.   Answer 50 km
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If a person walks at 14 km/hr instead of 10 km/hr, he would have walked 20 km more. The actual distance travelled by him is :