After figuring how to plant your 10 trees in 5 rows, the tree keeper walks up to you.

I like your idea, but sometimes I get vicious squirrels that come and steal all the fruit off it...

I am installing some garden path such that it is harmless to humans but will shock squirrels. (This means the squirrels won't pass over it.) Can you place those 10 trees along 5 lines of straight garden path so that there are 4 trees on each garden path and there are some trees on the inside?

How would you arrange the trees this time?

Here's one solution:

To describe the points... let's use a cartesian graph.

The 10 points are:

01) (0,4)
02) (-2,2)
03) (2,2)
04) (0,1)
05) (-4,0)
06) (-2,0)
07) (2,0)
08) (4,0)
09) (-6,-2)
10) (6,-2)

The 5 lines that they fall on (each line having 4 points) are:

y=0 (containing points 5, 6, 7, and 8)
y=(1/2)x + 1 (containing points 3, 4, 6, and 9)
y=(-1/2)x + 1 (containing points 2, 4, 7, and 10)
y=x + 4 (containing points 1, 2, 5, and 9)
y=-x + 4 (containing points 1, 3, 8, 10)

And of course... the lone tree in the middle is at point 4 (0,1).

Posted by SilverKnight on 2003-10-30 23:13:26