A and B runs around a circular track. A beats B by one round or 10 minutes. In this race, they had completed 4 rounds. If the race was only of one round, find the A's time over the course:
Select the correct option
A) 8.5 min	B) 7.5 min	C) 1.5 min	D) 9.5 min	E) 4.5 min
Explanation:   B runs around the track in 10 min.   i.e , Speed of 7.5 min = 10 min per round   A beats 7.5 min by 1 round   Time taken by A to complete 4 rounds   = Time taken by 7.5 min to complete 3 rounds   = 30 min   A's speed = 30/4= 
<gadget id="calculator">30/4</gadget>
<output>15/2 = around 7.5</output>
7.5 min per round   Hence, if the race is only of one round A's time over the course= 7 min 30 sec   Answer: 7.5 min
<result>B</result>
A and B runs around a circular track. A beats B by one round or 10 minutes. In this race, they had completed 4 rounds. If the race was only of one round, find the A's time over the course: