(a) and (b) looks correct
(c) Here's how my table looks like:
15 -18 324
27 -6 36
28 -5 25
34 1 1
42 9 81
52 19 361
SUM 828
(d) Take the sum of 828 and divide it by 6 to get 138. Now take the square root of 138 to get the standard deviation:
sqrt(138) ≈ 11.75
1/2(12-v)=1/6(v-6)
6-1/2v=1/6v-1
7=2/3v
v=21/2 or 10.5
Answer:
The total area (including the area of the circle) would be 16 × 16 = 256 square centimetres.
The area of the circle would be (taking the value of pi as 3.14) is 200.96 square centimetres
The area of the shaded region would be 256 - 200. 96 = 55.04 square centimetres
