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Cultivate your creativity to find that SHAZAM moment

  • Published
  • By Lt. Col. Brent French
  • 6th Security Forces Squadron commander
You are given nine gold coins. They all look identical, but one is half a gram lighter than the other eight. The weight difference is impossible to measure by human touch. You are then given a scale that looks like the scales of justice. The task is to find the light coin, by making only two weighings. That means you put "x" coins on the scale once, get feedback, remove the coins, put a new quantity on the scale, get feedback, and you're done.

Before you solve the riddle, I have one more thing to say. I want you to pay attention to when and how you solve it, and here's why.

I couldn't solve the riddle until I was driving, listening to the radio and spacing out; then SHAZAM the answer hit me. I learned that day that I do my best thinking while driving.
My challenge isn't just about dividing up piles of coins. It's about learning when your brain works most efficiently. This moment of self revelation has helped me repeatedly, and one of my best SHAZAM moments helped get children's bike helmet laws passed in New Hampshire.

In 2004 a research team published the results of the largest observational study on children's helmet usage ever performed in the United States. Since bicycling is the fifth leading cause of death for children, the team studied the safety practices of 8,159 bicycling kids.

Overall, 41 percent of those observed wore helmets. Forty five percent of kids in the 20 states that had helmet laws actually wore helmets, while 39 percent of kids wore helmets in states without laws. The team recommended 30 more states pass helmet laws, but I was unimpressed with the numbers at just a 6 percent improvement, and dug deeper.

As it turns out there's a difference between wearing a helmet and wearing it right; only 65 percent wore helmets properly. The probability of finding a child correctly wearing a helmet was 26 percent.

Since a helmet will prevent a fatal head injury 88 percent of the time, I ran the numbers through a Monte Carlo simulation (basically like rolling dice 10,000 times) and came to a conclusion. If 30 more states passed helmet laws, the nation could expect to save one more child every three years.

I was crushed by these anemic results. It appeared helmet laws were a waste of time and this caused a personal ethics minicrisis. Did I want to be the Cruella DeVille of bike safety and advocate against kids helmets? As a father of two young girls this position was unthinkable. I agonized, I lost sleep and then I remembered to get in the car and drive aimlessly until my wanderings provided the SHAZAM answer I looked for. I rushed back to my spreadsheets. 

Comparing helmet laws with seatbelt laws saved the day. Forty nine states have seatbelt laws with live free or die, New Hampshire being the exception.

In 2001, 1,686 children died in auto fatalities, twenty times the number of bike related fatal head injuries. But kids spend a lot more time in cars than riding bikes...the exposure rate is much higher.

The automotive fatality rate is 55 per 100 million opportunities. The probability of a fatal bike accident is quite close, 19 per 100 million opportunities. My logic was, if states were going to legislate seatbelt use then it makes sense to legislate helmet use for kids.

We presented our findings to a state representative from New Hampshire. In 2006, partially as a result of our efforts, the Granite State enacted mandatory helmet use for cyclists who are under the age of 16.

The moral of the story is that self awareness led to a breakthrough moment that turned a bad situation into a great one.

I may be guilty of sneaking veiled safety messaging into this article, but I really do want you to work on the nine coins riddle so you can figure out when you do your best thinking. The Air Force needs every ounce of your brainpower as we deliver Global Reach to protect our national interests.

Answer to the riddle: Divide the nine coins into three stacks of three coins. Call them stack A, B and C. Weigh stack A vs. stack B. This is your first weighing out of the two possible weightings. There are three possible outcomes, A is heavier than B; or B is heavier than A; or A weighs the same as B.
Let's assume that A is heavier than B, so this means the light coin is in stack B. Divide the three coins in stack B into piles of one coin each called coin B1, B2 and B3. Weigh B1 against B2. This is your second weighing of two possible weightings. There are three possible outcomes. If B1 is heavier than B2, then B2 is the light coin. If B2 is heavier than B1, then B1 is the light coin. If B1 equals B2, then B3, not being weighed, is the light coin.