Mar 2011
64 with 2 4s
31/03/11 10:09
Using only two 4's how would you get 64? You can use standard mathematical functions found on a calculator - plus, minus, multiply, divide, to the power, log, square root, factorial.... Cannot use trigonometry or any other digit.
(posted on Facebook on 3/31/2011)
(posted on Facebook on 3/31/2011)
Second Lap Speed
10/03/11 10:19
You drive a car 30 mph on a 1 mile lap. How fast must you drive the 2nd lap to average 60 mph for both laps?
(Matt Semrad had posted this as a response to my previous puzzle in Facebook)
(Matt Semrad had posted this as a response to my previous puzzle in Facebook)
Two trains colliding
10/03/11 10:17
A bullet train starts from Atlanta to San Diego at 200mph. A freight train starts an hour later from San Diego for Atlanta at 80 mph. When they meet, which train is closer to Atlanta? (note that the actual distance does not really matter)
(posted on Facebook on 3/10/2011)
(posted on Facebook on 3/10/2011)