Addition, I would use the principles of addition.
Pq= 10.5, qr=31.5, rs=10.5, sp=31.5
Answer:
σX = 3161
Step-by-step explanation:
The standard deviation is the square root of the multiplication of each probability multiplied by the squared difference between the values and the mean.
In this question:

Rounding to the nearest dollar, σX = 3161
Answer:
32 in^2.
Step-by-step explanation:
Area = area of the triangle + area of rectangle
= 1/2 * 4 * 6 + 4 * 5
= 12 + 20.