Camino del Norte part 7

Logic Puzzle

You have a calculator that has three buttons only. Here is what they do:

• Add 5 to the last number in the register.
• Add 7 to the last number in the register.
• Take the square root of the last number in the register.

The register starts at 0. How can you get to the numbers 2, 10 and 14, in that order? You may have other numbers in between.

Camino del Norte part 7

Day 7 on the Camino del Norte, March 24, 2026, began at the Izarra Albergue in Caborredondo. After breakfast, Lena, Thorgen, Steph, Rahel and me headed out and walked together for a while. Somehow this group of five became two groups as separated by age. I walked with Rahel, a hearty woman from Switzerland while the three younger pilgrims were somewhere ahead.

The walking was lovely. Much of the day we walked for long stretches on soft sandy beaches. Rahel shared she had never gone anywhere by herself her many years of married life. Her husband was not exactly enthusiastic about her decision to do the Camino but never said no either. So, she left to do it, with only a promise to return by a certain date about four weeks later. These are pretty much the same circumstances I did my Camino trip of 2024.

Rahel was doing the Camino on a limited budget, which necessitated carrying food and minimizing restaurants. It made it a little uncomfortable when I suggested we stop for lunch in Comillas and she pulled food out of her backpack to eat at the outside table. Of course, I offered to pay for anything she wanted, but she didn’t evidently want to be a mooch.

In looking back over my entire trip, this was the only time I walked with the same person all day long. It’s not easy finding someone who walks at your speed, is agreeable to your desired distance to cover and you can get along with for hours. Sometimes, I suspect others find me boring, which makes it hard to find hiking partners. It should be noted that I was 60 at the time of this trip and most people doing the Camino were half my age.

Eventually, we made our way to San Vicente de la Barquera and stayed at the Nómada Albergue. I saw advertisements for this Albergue many times over the last few days. After we arrived, we found the other three from the morning group already there relaxing. The Albergue was large, comfortable with nice amenities but was more corporate in feeling than small family-owned ones.

By the time I was cleaned up and ready to hit the town, the three younger members from the previous day were already out. Rahel was still there who said they went out to buy groceries to make dinner. I asked her if they invited us. She replied “no.” She seemed a bit sad about it. I suggested that we let the young people enjoy themselves and we could do our own thing. This she happily agreed to and we walked around the coastal town and enjoyed dinner. This time she didn’t object to spending a little money.

When we returned, we found the three young pilgrims enjoying their homecooked meal at the Albergue. We chatted at the same table. Thorgen, the young cheerful German man, evidently felt awkward at the situation and invited us to join them, to which the two young women agreed, perhaps not wanting to look like holdouts. I ate a little as the meal was coming to an end anyway and they had plenty of food. Rahel declined.

Despite the awkwardness of the division of the group, it was a very nice day. One of my favorites, both in terms of scenery and socially. The distance covered was 27.6 kilometers.

Logic Puzzle Answer

I’m sure there are multiple solutions. The following is just one.

• Add 5 three times. This will bring you to 5*3 = 15.
• Add 7 three times. This will bring you to 15 + 3*7 = 36.
• Take the square root. This will bring you to √36 = 6.
• Add 5 two times. This will bring you to 6 + 2*5 = 16.
• Take the square root. This will bring you to √16 = 4.
• Take the square root. This will bring you to √4 = 2. This accomplishes the first part.
• Add 7. This will bring you to 2+7 = 9.
• Take the square root. This will bring you to √9 = 3.
• Add 7. This will bring you to 3+7 = 10. This accomplishes the second part.
• Add 7 twice. This will bring you to 10 + 2*7 = 24.
• Add 5 five times. This will bring you to 24 + 5*5 = 49.
• Take the square root. This will bring you to √49 = 7.
• Add 7. This will bring you to 7+7 = 14. This accomplishes the third part.

Acknowledgement

This puzzle was found on the Ted-Ed YouTube channel video titled "Can you solve the giant cat army riddle? - Dan Finkel".