geometry
posted by guy on .
bulletin board border
please help me. i would like to make a geometry bulletin board that has a a border of circles, triangles and squares. i know that 20 shapes will fit across the board and that 12 shapes will fit down the board . if i start in the top left hand corner with a circle, followed by a triangles, then a square, and repeat this pattern all around the board, how many of each shape will i pattern all around the board, how many of each shape will i need? explain your solution using words and pictures.

sorry, no pictures here.
If 20 fit across top and bottom, that's 40.
The sides hold 12, but top and bottom are already taken at the corners, leaving room for 10 more along the sides. That makes 20 more for both sides.
So, you will have 60 pictures in all.
Since you have 3 different pictures, I guess you can figure how many of each you will need . . .
you could also have figured this out by spending 5 minutes drawing the border . . . 
Three letters are chosen at random from the letters P, A, N, S, O, L. What is the size of the sample space of this experiment? Assume that the order of the letters matters. That is, PAN is different from APN.