You go on a ride where the first half is up hill & second half is into wind
Rank following 3 in order of fastest average speeds
1st half 5mph 2nd half 15mph
6mph & 12mph
7ยท5mph & 10mph
Looks easy but 9 out 10 mamils get this wrong . Assume each half is 15 miles long & compare total times
4 hours, 3.75: 3.5
Fastest is last & slowest firat