A man covered a certain distance at some speed. Had he moved 3 kmph faster, he would have taken 40 minutes less. If he had moved 2 kmph slower, he would have taken 40 minutes more. The distance (in km) is:	Pick:
A) 35	B) 36 2/3	C) 37 1/2	D) 40	E) 45
Explanation:   Let distance = x km and usual rate = y kmph.   Then,	x/y-x/y + 3=40/60 =&gt;2y(y + 3) = 9x ....(i)   And, x/y -2-x/y =40/60 =&gt;y(y - 2) = 3x ....(ii)   On dividing (i) by (ii), we get: x = 40.   ANSWER IS 40
<result>D</result>
A man covered a certain distance at some speed. Had he moved 3 kmph faster, he would have taken 40 minutes less. If he had moved 2 kmph slower, he would have taken 40 minutes more. The distance (in km) is: