A delivery truck from the post office is sent to the airport to meet a cargo plane at its planned arrival time. The plane lands ahead of schedule and its contents are brought toward the post office by bicycle. After a half hour, the bicycle meets the truck and the mail is transferred.
The truck returns from the post office 20 minutes early. How early did the plane arrive? (Assume all transactions are instantaneous)
The delivery truck arrived back 20 minutes early, so it would have taken 20 minutes to go from where it met the bicycle to get to the airport and back. Therefore, the bicycle and truck met when the truck was 10 minutes from the airport. Adding those 10 minutes to the 30 minutes the truck had already driven to meet the bicycle means the plane arrived 40 minutes ahead of schedule.
Supposedly this is given as a test in Japan. I have no idea if that’s accurate.
There are 8 people who have to cross the river on a raft.
1. Policeman 2. Thief 3. Father 4. Boy 1 5. Boy 2 6. Mother 7. Girl 1 8. Girl 2
The rules are:
Only two people can cross at a time. Only the adults can operate the raft. The father can’t be with the girls unless the mother is there. The mother can’t be with the boys unless the father is there. The thief can’t remain with anyone unless the policeman is present.
Mario is testing out a new car at the racetrack. His grandmother took it for a mile lap and averaged 30mph. How fast does Mario have to drive in the second lap to average 60mph for the two miles?
90mph is an alluring answer, but it’s impossible. At 90mph the second lap would take 40 seconds. If Grannie’s first lap at 30mph took 2 minutes, traveling 2 miles in 2 minutes and 40 seconds is an average speed of 45mph. Traveling an average speed of 60mph for 2 miles would take 2 minutes and since the grandma’s lap took all of those 2 minutes, even if Mario could break the sound barrier he wouldn’t be able to average 60mph.
Fence. Fences keep ne’er-do-wells out and protect people inside. A fence is a person who buys stolen goods to later resell them for a profit. Those who fence practice the sport of fencing. En garde! And people don’t like it when you sit on the fence in a heated debate. (Believe me, I speak from experience)
Someone preserving food. The two most common ways of preserving food are canning and freezing. So when you preserve food, if you can can it, you do, otherwise you freeze it.