Riddles, one at a time
Growing Frame
Steps 4 to 19 are not shown. How many tiles will step 20 have?
Look at the side length of each frame. How does it grow from step to step?
84
Step 20 is a 22 × 22 frame: 4 sides of 21 tiles, 4 × 21 = 84.
Yesterday's Clue
What day is tomorrow?
Work out yesterday first, then count forward one day at a time.
Thursday
Yesterday was Tuesday, so today is Wednesday: tomorrow is Thursday.
Lighthouse Flashes
A lighthouse flashes evenly. From the 1st flash to the 6th takes 5 seconds. How long from the 1st flash to the 11th?
Count the gaps between flashes, not the flashes.
10 seconds
Flash 1 to flash 6 is 5 gaps, so each gap is 1 second. Flash 1 to 11 is 10 gaps.
The Stone Garden
Which gate leads to the fountain?
GATE C
Every other gate is sealed off by a stone wall.
Mirror Clock: 13:31
How many minutes until the clock shows the next mirror time?
Try the next hour: 14:??
70 minutes
The next mirror time is 14:41, 70 minutes later.
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.