Step-by-step explanation:
where are the triangles
1) Mean
The mean is given by the sum of the data divided by the number of data (4, in this case):

2) Standard deviation
The standard deviation is given by:

where

is the mean, that we already found at point 1), and N=4. Substituting data, we have:

Answer: 4
Step-by-step explanation:
Answer:
336 sq un
Step-by-step explanation:
The area of a rhombus is pq/2 where p and q are the diagonals.
you have:
p = 12 + 12 = 24
q = 18 + 10 = 28
so the formula would be:
24 * 28 / 2 = 336 sq un