Speed-freaks

1. You drive to the shops at 20 mph and return by the same route at 30 mph. Discounting the time spent shopping, what was your average speed?

(easy)

2. If you drive to the shops at 20 mph, how fast must you go (again returning by the same route) for your average speed to be 40 mph?

(slightly more taxing)

1. 24 mph
2. infinite

Originally posted by Mathurine
[b]1. You drive to the shops at 20 mph and return by the same route at 30 mph. Discounting the time spent shopping, what was your average speed?

(easy)

2. If you drive to the shops at 20 mph, how fast must you go (again returning by the same route) for your average speed to be 40 mph?

(slightly more taxing)[/b]

Originally posted by sonhouse
like he said. There was a problem just like this posted less than a week ago.

Eh, I posted repeats as well, no biggie..