Answer:
1 flier
Explanation:
David posted 14 fliers last week.
We can find the remaining fliers by subtracting total fliers to the fliers posted.
So there are 60 - 14 = 46 fliers remaining.
Now,
This week, he posted 45 of the remaining fliers.
So, he still has 46 - 45 = 1 flier not posted.
So, he has 1 flier which is not posted.