Riddles, one at a time
Bead 100
Beads 13 to 99 are not shown. The pattern teal, teal, gold, gold, gold repeats. What colour is bead 100?
Count in groups of 5.
Gold
100 = 19 × 5 + 5: bead 100 is the 5th bead of its group, and the 5th is gold.
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.
Fewest Tokens: Pay 11
Which tokens pay 11 with the fewest tokens?
Biggest first is not always fewest. Try every pair.
5 + 6
Just 2 tokens. Biggest first, 9 + 1 + 1, needs 3.
Flatbread Pan
A pan holds 2 flatbreads. Each side needs 1 minute. How few minutes can it take to cook 3 flatbreads on both sides?
Do not wait for one flatbread to finish before starting the third.
3 minutes
Minute 1: A and B. Minute 2: A's other side and C. Minute 3: the other sides of B and C.
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 Triangles?
How many triangles are in the figure?
15
Single pieces plus every combined shape: 15 in all.