Final answer:
Adam has finished 190 puzzles.
Step-by-step explanation:
To find out how many puzzles Adam has finished, we first need to calculate 95% of the total number of puzzles in the book.
This can be done by taking 95% of 200 puzzles:
95% of 200 puzzles
= 0.95 x 200
= 190 puzzles
Therefore, Adam has finished 190 puzzles.