Riddles, one at a time
Growing Stairs
Steps 4 to 9 are not shown. How many tiles will step 10 have?
Each new step adds a column one tile taller than the last.
55
1 + 2 + 3 + ... + 10 = 55 tiles.
The Lamp and the Wall
Which shadow appears on the wall?
C
Each row's tallest stack sets the shadow.
Shaded Part: The Triangle
What fraction of the square is gold?
Cut the triangle down the middle and move one half.
1/2
The triangle has the full base and full height of the square, so it is half: 8 of 16 squares.
The Brass Grilles
Read the holes row by row. Which grille shows a real word, and what is it?
B: MAPLE
Read the holes row by row, left to right.
Inside the Loop: Four Gems
Which gem is INSIDE the loop?
Trace a straight line from a gem to the edge and count the walls.
A
A line from A to the edge crosses the wall once (odd): A is inside. B, C and D reach the edge without crossing.
Mirror Odometer: 15951
How many more km until the next mirror number?
The middle digit is already 9, so it cannot go up. What has to change instead?
110 km
The next mirror number is 16061: 16061 − 15951 = 110.