Jack and Jill are marathon runners. Jack can finish a marathon (43 km) in 4.5 hours and Jill can run a marathon in 4.3 hours.What is the ratio of their average running speed? (Jack: Jill)  Choose the correct option:
A) 14/15
B) 43/45
C) 4/5
D) 5/4
E) Cannot be determined
Average Speed of Jack =Distance/ Time   = 43 /(9/2) = 86/9   Average Speed of Jill = 43/(4.2) = 10   Ratio of Average speed of Jack to Jill = (86/9)/10 = 86/90 = 43/45   Answer 43/45
<result>B</result>
Jack and Jill are marathon runners. Jack can finish a marathon (43 km) in 4.5 hours and Jill can run a marathon in 4.3 hours.What is the ratio of their average running speed? (Jack: Jill)