Brain Teasers 55 - Puzzle Prime

Slowest Horse

Section: Brain Teasers Category: Lateral

Difficulty: Medium

Two friends made a bet whose horse is slower. After wondering for days what is the fastest and fairest way to figure out who wins the bet, they finally decided to ask a famous wise hermit for help. Upon giving them his advice, the two friends jumped on the horses and started racing back to the city as fast as they could. What did the hermit say?

SOLUTION

He told them to switch their horses and whoever gets to the city first will win the bet.

Unknown Author April 13, 2017

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Sisters and Brothers

Section: Brain Teasers Category: Deduction

Difficulty: Easy

In one family there are 6 sisters and each of them has one brother. How many children are there in the family?

SOLUTION

There is just one brother and therefore there are 7 children in the family.

Unknown Author April 4, 2017

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A Maze Puzzle for the Day

Section: Brain Teasers Category: Insight

Difficulty: Hard

Here’s a little maze puzzle I originally built a couple of years ago, that seems apropos to reprise now:

Can you make it from the A in the top left of this grid to the Z in the bottom right, always going either up one letter (for instance, A to B or G to H) or down one letter (for instance, N to M)? The alphabet wraps around, so you can go from Z up to A or A down to Z too. Try as hard as you can (and remember that you can always work backward if you get stuck forwards), and see where you get!

Remark: Solving the maze is not the same thing as solving the puzzle. Read those instructions carefully!

SOLUTION

Notice this puzzle is published on April 1st. Actually, it doesn’t have a standard solution. If you connect every two consecutive letters which appear next to each other in the grid, you will get two disconnected components, one of which contains the START and the other contains the END. The first component has 5 dead-ends – at letters A, P, R, I, L, and the second component has 5 dead-ends – at letters F, O, O, L, S. These two spell out “April Fools”, which is the real solution of the maze.

Steven Stadnicki April 1, 2017

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How Many Letters

Section: Brain Teasers Category: Deduction

Difficulty: Easy

How many letters does the correct answer to this puzzle contain?

SOLUTION

Four – the only number which has the same number of letters as the number itself.

Unknown Author March 22, 2017

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Seven Bridges

Section: Brain Teasers Category: Insight

Difficulty: Advanced

This is a map of old-time Kongsberg. The green shapes are bridges which connect the different parts of the city. Can you find a path through the city which goes through every bridge exactly once?

SOLUTION

No, you cannot. Notice that, except for the first city and the last city section you finish, the number of bridges used in every other section is even. However, there are three sections with an odd number of bridges, and therefore you cannot use all bridges exactly once.

Unknown Author March 19, 2017

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Funky Mate

Section: Brain Teasers Category: Chess

Difficulty: Medium

Place only 2 rooks and 1 knight on the board, so that the Black player is mated.

SOLUTION

You can place the rooks on c5 and e5, and the knight on f5.

Unknown Author March 10, 2017

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Apples or Strawberries

Section: Brain Teasers Category: Insight

Difficulty: Easy

What is heavier – 1 pound of apples or 1 pound of strawberries?

SOLUTION

They are equally heavy – 1 pound each.

Unknown Author March 1, 2017

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Missing Pawns

Section: Brain Teasers Category: Chess

Difficulty: Advanced

White to play and mate in 4 moves.

Remark: The position on the diagram is one which occurs in actual play.

SOLUTION

Notice that the black queen and the black king have switched positions. However, this can happen only if some pawns have been moved. Therefore, we can conclude that the bottom row on the diagram is actually the 8th row of the chessboard. All black and all white pieces have reached their respective opposite sides of the board.

Now, White’s first move is Kb8-d7. The only moves black can play are with the knights. If Black plays Kb1-a3, Kb1-c3 or Kg1-h3, white mates in 2 more moves – Kd7-c5 and Kc5-d3. If Black moves Kg1-f3, then after Kd7-c5 Black can delay the mate by playing Kf3-e5. However, after the white queen takes it with Qxe5, Kc5-d3 is unavoidable.

Unknown Author February 19, 2017

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Marathon

Section: Brain Teasers Category: Insight

Difficulty: Easy

You are running a marathon and right at the finish line, you pass the runner in the 2nd position. In which place do you finish the marathon?

SOLUTION

You finish 2nd. Before passing the runner you were at 3rd place.

Unknown Author February 16, 2017

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Snail on a Tree

Section: Brain Teasers Category: Insight

Difficulty: Medium

A snail is trying to climb a 10-meter poll. Every day it climbs 4 meters up and then during the night slides 3 meters down. How many days are needed for the snail to get to the top of the poll?

SOLUTION

Seven days only. After the sixth day, the snail would have climbed 6 meters. During the seventh day, it will climb 4 more meters and will get to the top.

Unknown Author February 4, 2017

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