“I see the elephant seal,” said Bob. “But now the wind has shifted, and I see a polar bear with its head in the snow. What you saw as a tail is now the bear’s head, and the elephant seal’s huge schnoz has become the bear’s tail. The animal has totally reversed direction!” Alice was glad that Bob was picking up the new topic of discussion. Alice had not been looking forward to two more hours of Bob’s statistical diversions.
The two passengers worked together processing insurance claims, and Bob had spent the morning trying to explain the company’s new statistical software to Alice. She had lobbied hard to have work pay for them to attend this conference in Los Angeles. Alice wasn’t about to let Bob turn their time away from work into a technical lecture.
“It’s cool how one’s perception of a thing can change so quickly and vary from person to person,” mused Alice, hoping to keep the conversation away from statistics. As she was speaking a dash light popped on. “Uh oh. It looks like the tank is running low.”
“We’ll be alright. It can’t be too far to the next gas station,” said Bob. Alice hoped this delay wouldn’t come between her and the hotel’s dinner buffet. They drove a few more miles until Bob spotted a sign. “Hey, pull over at the next rest stop, gas is only $2.85,” said Bob.
“Ohh,” said Alice, suddenly forgetting her frustration with Bob. “If you look at it right, that gas price looks a lot like a 6 to me.”
“What do you mean?” replied Bob. “I’m not sure the business office would let us claim six dollar gas as an expense.”
“It just feels like a 6. The 8 and 5 feel like a 3, which, together with the 2, makes a 6.”
“But you just made that up,” protested Bob. You could combine those numbers any which way.”
“What’s wrong with that?”Alice pulled off the highway into the rest stop, looking for other number transformations. She stopped the car next to the gas pump and inserted the nozzle into the car’s tank. Seeing a truck’s license plate, she pointed it out to Bob and said, “Here’s another example. Look at that license plate over there. ABK 1372. Ignoring the initial letters, that number looks like an 18 to me. 2 and 7 make 14; 14 and 3 make 17;...”
“And 17 and the final 1 make 18.” Bob finished the thought.
“Nice.” Alice finished paying and the two drove back onto the highway.
“I like the freedom you have to morph one number into another. But there have to be limits to how you can combine the numbers,” said Bob.
“Of course there are,” said Alice. “You can only add, subtract, multiply, and divide. And you have to use all the digits to get your answer. There has to be a balance between rules and freedom.” As they drove on, Alice noticed a sign. “It looks like Los Angeles is 172 miles away. We probably won’t be there for another three hours. I’m not sure we’ll make dinner,” she said, discouraged.
“The number 172 looks like a 13 to me,” said Bob. “Can you see how I did it?”
“I see it. And it looks like a 21 to me! You’re getting the hang of it!” Alice and Bob’s new game kept them busy for the rest of the ride. Alice realized that if she missed the buffet and ended up with takeout, it would be alright.
This game is perfect for a road trip. It requires no equipment, is collaborative, and is responsive to the environment. It is called 25 - in reference to the classic elementary math game 24.
To play this game, the players work together to create the numbers from 1 to 25 - the target numbers - from numbers they see. For each target number players find some number in their environment: a license plate, a date, a VIN number, etc. Dropping all letters and punctuation, players must combine the digits using the four arithmetic operations of addition, subtraction, multiplication, and division to equal the target number. Each digit must be used exactly once. Players proceed from target number 1 to target number 25 in order.
A game may start
1. Exit 76. $$1 = 7 - 6.$$
2. A date 6/12. $$2 = (6\div 2) - 1.$$
3. A price $\$ $2.99. $$3 = (9\div 9) + 2.$$
Happy trails and enjoy the game!