Q2. The second question gives you the same amount of fence sections but only three sides of a rectangle need to be filled. This means the list becomes -1 on one side and +2 on the other.here is this list:
19x2=38
18x4=72
17x6=102
16x8=128
15x10=150
14x12=168
13x14=188
12x16=192
11x18=198
10x20=200 This is the highest point before the total falls again.
9x22=198
Q3. The shape of the wallmeans that 10m worth of fencing is used to make a shape that is equal to the size of the wall. This question must b split into two shapes. One which is 8x10 and the other which is made of only thirty fence sections. The list is +1 and -2:
1x28=28
2x26=52
3x24=72
4x22=88
5x20=100
6x18=108
7x16=112 These two are the highest total before adding the second shape
8x14=112 which when added makes a total of 192.
9x12=108
10x10=100
11x8=88
12x6=72
13x4=52
14x2=28
Extension
the curved fences would not help because for every curve you make you have an inside and an outside that cause the area to be the same as it was before.