A rectangle measures 30 feet by 20 feet and has a post at each corner. If posts are placed 2 feet apart. How many posts will there be in all?

You would need 34 posts. I drew this out and then added up each post. Note that some of the posts will be less than two feet apart because there has to be a post on each corner.

Ignoring the corner posts, there are 14 posts along each long side, 9 posts along each short side and the 4 corner posts for a total of 2(14) + 2(9) + 4 = 50

To find out how many posts there will be in all, we first need to determine the number of posts on each side and then add them all up.

The rectangle measures 30 feet by 20 feet, so the length of each side is as follows:
- The length of the longer side is 30 feet.
- The length of the shorter side is 20 feet.

Since the posts are placed 2 feet apart, we need to divide the length of each side by the length of each gap between the posts to calculate the number of posts on each side.

For the longer side (30 feet), we divide it by the gap length (2 feet) and add 1 to account for the starting post:
30 feet / 2 feet + 1 = 15 + 1 = 16 posts.

For the shorter side (20 feet), we do the same calculation:
20 feet / 2 feet + 1 = 10 + 1 = 11 posts.

Now, we can find the total number of posts by adding up the posts on each side:
16 posts (longer side) + 11 posts (shorter side) = 27 posts in total.

Therefore, there will be a total of 27 posts in all.