The sum is 12x3+18x2-10x+8
Answer:
a) For this case we can use the definition of weighted average given by:

And if we replace the values given we have:

b) 
c) 
Step-by-step explanation:
Assuming the following question: "One sample has a mean of M=8 and a second sample has a mean of M=16 . The two samples are combined into a single set of scores.
a) What is the mean for the combined set if both of the original samples have n=4 scores
"
For this case we can use the definition of weighted average given by:

And if we replace the values given we have:

b) what is the mean for the combined set if the first sample has n=3 and the second sample has n=5
Using the definition we have:

c) what is the mean for the combined set if the first sample has n=5 and the second sample has n=3
Using the definition we have:

Multiply the denominator by the number in front of it and then add it to the numerator. (6•2=12+5=17). The denominator stays the same. Your answer is 17/6. Hope this helped!
Answer:

Step-by-step explanation:

Answer:
$80.00
Step-by-step explanation:
We have: 120 ft = 40 yards (divide the length value by 3
)
=> Jerome will cost: 40 x $2.00 = $80.00 for the fencing.