CalTheGreat

Check out Melody's and a guest's good answer for the first 2:

Okie dokie!

Although I am not so great on these problems, I have found a very useful article that you can use to solve this problem.

Here is the link:

I'm not 100% sure about this

All of the digits digits greater than 100 need AT LEAST a 0 or 9 with digits 1 and 8

Therefore, the multiples that work are:

18

81.

Okay, Melody.....

Since the new shape has to have the greatest possible side lengths that add up to the perimeter, 160 ft...

The square's side lengths will be 40ft by 40ft

The area of the square would be1600 square feet.... let's see how much it enlarged.

1600-1200=400

It enlarged by 400 square feet.

I think my computer lagged.... on another device, I can see the second one, and I've given you a hint on it on your other post ;D

This was posted here, and it has a very good answer that is understandable.

Okay, thanks!

Here's a hint.

We need to use the Pythagorean Theorem to figure out the lengths of all of the side lengths. Then, add the side lengths and then multiply that by 2.5. Tell me what you get, and I will check it. :D