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 2 minutes. What is the ratio of speeds A:B:C?
Select the correct option.
A) 3:4:5	B) 4: 5:20	C) 5:4:3	D) 4:6:5	E) 12:15:25
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= 4 laps in 4 minute;   B's speed (distance)/(time) = 10/8 = 5/4 lap per minute = 5 laps in 4 minutes;   C's speed (distance)/(time) = 10/2= 
<gadget id="calculator">10/2</gadget>
<output>5</output>
5 lap per minute= 20 laps in 4 minutes/   Therefore, the the ratio of speeds A:B:C is 4: 5:20.   Answer: 4: 5:20.
<result>B</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 2 minutes. What is the ratio of speeds A:B:C?