A boat travelled upstream of 90 miles at an average speed of (v-3) miles/hr and then travelled the same distance downstream at an average speed of (v+3) miles/hr. If the trip upstream took half an hour longer than the trip downstream, how many hours did it take the boat to travel downstream ?
A) 2.5
B) 2.4
C) 2.3
D) 2.2
E) 2.1
- What is the short method to solve this problem ? Plugging in and Algebra makes it too long and tedious. Is there a shorter method ?
IMO:A
A) 2.5
B) 2.4
C) 2.3
D) 2.2
E) 2.1
- What is the short method to solve this problem ? Plugging in and Algebra makes it too long and tedious. Is there a shorter method ?
IMO:A
