Puzzle 17
What number comes next in this sequence:
1 · 8 · 9 · 64 · 25 · 216 · 49 · ?
Puzzle 18
Each of these words can be split in half, and two letters can be placed in the middle to create a new six-letter word.
The four added pairs of letters, in order, spell an 8-letter word. What is that word?
lend
liar
pale
coin
For example:
door + ct = do + ct + or = doctor
suit + nl = su + nl + it = sunlit
Puzzle 19
Starting with SOFT, change one letter at a time until you have the word LENS.
Each change leaves the other letters in their original places and must result in a proper word.
What is the minimum number of steps required to achieve this change?
SOFT
....
....
....
LENS
Puzzle 20
Can you make this equation correct by moving exactly one matchstick?
Note: this puzzle is not interactive, and the matchsticks cannot be moved. The matchstick layouts for each digit are:
