A, B and C start swimming in a pool simultaneously from the same end. To complete 10 laps, A takes 10 minutes, B takes 8 minutes and C takes 9 minutes. What is the ratio of speeds A:B:C?
Choose the correct choice from the following:	A) 3:4:5	B) 12:15:20	C) 5:4:3	D) 4:6:5	E) 36:45:40
The slowest one is A, then comes B and the fastest one is C. So, the the ratio of speeds A:B:C must be in ascending order. Eliminate options C, D, and E.   A's speed (distance)/(time) = 10/10= 
<gadget id="calculator">10/10</gadget>
<output>1</output>
1 lap per minute= 36 laps in 36 minute;   B's speed (distance)/(time) = 10/8 = 5/4 lap per minute = 45 laps in 36 minutes;   C's speed (distance)/(time) = 10/9 = 10/9 lap per minute = 40 laps in 36 minutes/   Therefore, the the ratio of speeds A:B:C is 36:45:40.   Answer: 36:45:40.
<result>E</result>
A, B and C start swimming in a pool simultaneously from the same end. To complete 10 laps, A takes 10 minutes, B takes 8 minutes and C takes 9 minutes. What is the ratio of speeds A:B:C?