CarTalk.com Blogs Car Info Our Show Deals Mechanics Files Vehicle Donation

Puzzler March 27th. Delivery Van

Greetings from Sunny San Diego,

Unfortunately, I missed the answer to the Delivery van puzzler. Did the van, in fact, keep rolling down the hill? Thanks for any info.

Here’s the answer. The drive shaft had broken, more precisely a U-joint broke - that was the gunshot sound. And now the transmission was no longer connected to the wheels. The drive shaft was dragging on the ground before it finally fell out.

Unless the driver jumped in and stepped on the brake…the van stopped at the bottom of the hill.

In other words park does not work without a drive shaft so the truck kept on rolling down the hill.

I’m not a big puzzle guy. There are enough problems to solve without adding more, so I’m not even thinking about how to measure 6 ozs from a 4 and a 9 oz container. So if you find out let me know.

I KNEW it! But we were 10 days in Glamis, CA in the sand dunes with no internet so I couldn’t answer.!! Thanks for your reply (ies).

This is an old puzzle from years ago. If you tilt a glass until the water reaches the top edge of the bottom and the water is on the lip of the glass it’s exactly half full. Half full in the 4 ounce glass gives you exactly 2 ounces. Pour that and then a full 4 ounce into the 9 ounce glass and you have exactly 6 ounces.

Hmm - doesn’t that mean you have a nice, perfectly straight glass? Not like any glass I own!

Here’s your solution… at the end of each step, I’ve marked the # of ounces in the 4 oz. glass and the 9 oz. glass as follows (ounces in 4oz glass/ounces in 9oz glass):

  1. Fill the 9 oz glass (0/9)
  2. Pour water from the 9 oz glass into the 4 oz glass until full (4/5)
  3. Empty the 4 oz glass (0/5)
  4. Pour water from the 9 oz glass into the 4 oz glass until full (4/1)
  5. Empty the 4 oz glass (0/1)
  6. Pour the 9 oz glass into the 4 oz glass (1/0)
  7. Refill the 9 oz glass (1/9)
  8. Pour water from the 9 oz glass into the 4 oz glass until full (4/6)

Your 9 oz glass now has 6 ounces of water in it.

Details…details. The puzzle clearly states that a 4 ounce and a 9 ounce glass are used. I chose to use straight sided glasses. It’s the solution that uses the least amount of steps and they sell straight sided glasses everywhere.