Riddles, one at a time
How Many Routes: One Cone
Moving only right or up, how many different routes lead from start to the gem?
Give the cone corner 0, then add the counts from the left and below.
8
There are 20 routes in all, and 12 of them pass the cone: 20 − 12 = 8.
How Many Routes: 2 × 2 Grid
Moving only right or up, how many different routes lead from start to the gem?
Each corner's count is the count to its left plus the count below it.
6
Add the ways from the left and from below: 3 + 3 = 6.
Mirror Clock: The Long Wait
4 hours 11 minutes
16:61, 17:71, 18:81 and 19:91 are not real times. The next is 20:02, 4 h 11 min after 15:51.
Inside the Loop: The Trapped Gem
Which gem is INSIDE the loop?
Count wall crossings on the way to the edge: odd means inside.
B
Gem B is inside; A, C and D sit in pockets that open to the outside.
Glass Overlay: Lines Cancel
Which card completes the grid?
Lines that appear on both cards disappear; all the other lines stay.
B
In each row, lines on both cards cancel and the rest stay. Row 3 gives card B.