Puzzle: The Four Friends

Four friends—Alice, Bob, Cindy, and Dave—decided to participate in a puzzle-solving competition. They were given a set of clues to determine the order in which they finished. Can you determine the correct order in which they finished, as well as their favorite colors and puzzle-solving times? 

Clues:

• The person who finished first took the least amount of time to solve the puzzle.
• Bob took longer to solve the puzzle than both Alice and Cindy.
• Dave’s favorite color is blue, and he finishes before the person whose favorite color is green.
• The person who finished second took twice as long as the person who finished third.
• The person who finished last had a favorite color of yellow.

Four friends

Solution:

To solve this puzzle, let’s examine the given clues and deduce the correct order of finish, favorite colors, and puzzle-solving times:

Let’s proceed step by step:

• From clue 1, the person who finished first took the least amount of time. Let’s label the friends as A (Alice), B (Bob), C (Cindy), and D (Dave).
• From clue 2, Bob took longer than both Alice and Cindy. Therefore, Alice and Cindy cannot be Bob.
• From clue 3, Dave finished before the person whose favorite color is green. Dave’s favorite color is blue, so the person who likes green must finish after Dave.
• From clue 4, the person who finished second took twice as long as the person who finished third. This means Alice, who finished third, took half the time of the person who finished second.
• From clue 5, the person who finished last had a favorite color of yellow.

Let’s use these deductions to solve the puzzle:

• Since Bob took longer than both Alice and Cindy, he could not finish first.
• Dave’s favorite color is blue, so he must be Bob.
• From clue 3, Dave finished before the person whose favorite color was green. Since Alice and Cindy cannot be Dave, Alice or Cindy must have green as their favorite color.
• From clue 4, Alice finished third and took half the time of the person who finished second. Since Dave is Bob and finished first, Alice must finish second.
• From clue 5, the person who finished last had a favorite color of yellow. Since Alice is accounted for, Cindy must have yellow as her favorite color.

Now, we have the following information:

• 1st: Dave (Bob)
• 2nd: Alice (Green)
• 3rd:
• 4th: Cindy (Yellow)

From clue 4, Alice took twice as long as the person who finished third. Therefore, Cindy took half the time of Alice.

• 1st: Dave (Bob)
• 2nd: Alice (Green)
• 3rd:
• 4th: Cindy (Yellow) (half the time of Alice)

Now let’s consider the remaining positions:

The only position left is third place, which means Cindy must finish third. Therefore, Alice took twice as long as Cindy.

• 1st: Dave (Bob)
• 2nd: Alice (Green)
• 3rd: Cindy (Yellow)
• 4th: Cindy (Yellow) (half the time of Alice)

Finally, we can conclude:

1. 1st: Dave (Bob)
2. 2nd: Alice (Green)
3. 3rd: Cindy (Yellow)
4. 4th: Cindy (Yellow) (half the time of Alice)

As for their favorite colors:

1. Dave’s favorite color is blue.
2. Alice’s favorite color is green.
3. Bob’s favorite color is unknown.
4. Cindy’s favorite color is yellow.

Solution of Four Friends

Note: The puzzle did not provide enough information to determine Bob’s favorite color.