After several try, I was able to solve this Japanese puzzle. Since I can't find a solution for this puzzle, I thought of writing one.
Please note that Island 1 refers to the Island where the couples are standing when the game starts. Island 2 is the middle island, and Island 3 is the finish line.
Here's how I was able to complete this puzzle.
1. Take the Japanese couple to Island 3.
2. Bring back the Japanese husband to Island 1.
3. Take the Scottish Couple to Island 2.
4. Return the Scottish husband to Island 1.
5. Take the Japanese husband to Island 2 with the Scottish husband.
6. Japanese husband should return to Island 1.
7. Bring the Irish couple to Island 2.
8. Take the Irish wife and the Scottish wife to Island 3.
9. Return the Scottish wife to Island 2.
10. Let the Irish husband pick-up the Japanese husband in Island 1 and return them to Island 3.
11. Bring the Japanese couple to Island 2.
12. Take the Japanese husband and the Scottish husband to Island 3.
13. Let the Irish wife return the boat in Island 2.
14. Scottish wife and the Japanese wife should be the one to take the boat in Island 3.
15. Irish husband will sail to Island 1.
16. Irish husband and Dannish husband will sail to Island 3.
17. Irish husband will return to Island 2 and pick-up his wife and sail back to Island 3.
18. Danish husband will sail to Island 1 to bring his wife to Island 3.
Please note that Island 1 refers to the Island where the couples are standing when the game starts. Island 2 is the middle island, and Island 3 is the finish line.
Here's how I was able to complete this puzzle.
1. Take the Japanese couple to Island 3.
2. Bring back the Japanese husband to Island 1.
3. Take the Scottish Couple to Island 2.
4. Return the Scottish husband to Island 1.
5. Take the Japanese husband to Island 2 with the Scottish husband.
6. Japanese husband should return to Island 1.
7. Bring the Irish couple to Island 2.
8. Take the Irish wife and the Scottish wife to Island 3.
9. Return the Scottish wife to Island 2.
10. Let the Irish husband pick-up the Japanese husband in Island 1 and return them to Island 3.
11. Bring the Japanese couple to Island 2.
12. Take the Japanese husband and the Scottish husband to Island 3.
13. Let the Irish wife return the boat in Island 2.
14. Scottish wife and the Japanese wife should be the one to take the boat in Island 3.
15. Irish husband will sail to Island 1.
16. Irish husband and Dannish husband will sail to Island 3.
17. Irish husband will return to Island 2 and pick-up his wife and sail back to Island 3.
18. Danish husband will sail to Island 1 to bring his wife to Island 3.
By the way, this solution will take you less than 7 mins. more or less around 2 mins only. It just so happened that in this round where I took the screenshot was the time I am taking notes of the moves I make for this topic. Thanks.
