speed

[ketkoag]

A and B go home from their school. Does A arrive home earlier than B?
1) A's home is 30 miles far than B's
2) B is 10% slower than A

[tohellandback]

IMO E
1.not sufficient. speed is required
2. not sufficient-distance required

together..let's say B's home is X miles from school
A's home-X+30 miles
let's say speed of A is 10, B's speed is 9
time taken by A=(X+30)/10
time taken by B=X/9
to check which one is greater
subtract one from the other
X/9-(X+30)/10= (10X-9X-270)/90=(X-270)/90 you see this value is positive for X>270 and negative for X<270
so not sufficient

[ketkoag]

IMO E as well. wanna confirm the answer..
thanks..

[kidcorpo]

A and B go home from their school. Does A arrive home earlier than B?
1) A's home is 30 miles far than B's
2) B is 10% slower than A

Non-math required way to solve:

1) Insufficient alone. Speed not given.
2) Insufficient alone. Distance not given.

Combined: If B lives 0.1 miles away from school, and A lives 30.1 miles away from school, B will obviously get there first! We need to know how far at least one of the homes are, otherwise B could be anywhere from right beside the school (0 time to get home) to 1000 miles away from school!