I would say A (7) but I’m not 100% sure.
Answer:
The probability distribution for x:"number of children per family for this income group" is:

Step-by-step explanation:
With the information given we have the relative frequencies of each category.
We know:

Answer:
A. 1/2 (20 x 50) + 1/2 (20 x 10), 2 (1/2 x 20 x 50) + 2(1/2 x 20 x 10)
B. 100
Step-by-step explanation:
Answer:
The answer is: X= -1 and y= -2 so <em><u>(-1,-2)</u></em>
hope this helps