Jack and Jill are marathon runners. Jack can finish a marathon (42 km) in 3.5 hours and Jill can run a marathon in 4.2 hours.What is the ratio of their average running speed? (Jack: Jill)	Answers
A) 14/15 B) 15/14 C) 4/5 D) 6/5 E) Cannot be determined
Average Speed of Jack =6/5istance/ Time   = 42 /(7/2) = 84/7   Average Speed of Jill = 42/(4.2)= 
<gadget id="calculator">42/(4.2)</gadget>
<output>10</output>
10   Ratio of Average speed of Jack to Jill= (84/7)/10 = 84/70 =6/5   Answer 6/5
<result>D</result>
Jack and Jill are marathon runners. Jack can finish a marathon (42 km) in 3.5 hours and Jill can run a marathon in 4.2 hours.What is the ratio of their average running speed? (Jack: Jill)