Answer:
Step-by-step explanation:
The given data set is:
Week 1: 600
Week 2: 300
Week 3: 500
Week 4: 900
The following are the steps to find the standard deviation:
Step 1. Jim enters the data and calculates the average or mean.
Step 2. Jim calculates the deviation from the mean by subtracting the mean from each value.
Data value (x) 
600 25
300 -275
500 -75
900 325
Step 3. Jim squares each deviation to remove negative signs.
Data value (x) 
600 625
300 75625
500 5625
900 105625
Step 4. Jim sums the squares of each deviation and divides by the count for the variance.
Step 5.Jim takes the square root of the variance to find the standard deviation.
Answer: 3, 2, 1, 0, -1
Step-by-step explanation:
3, 2, 1, 0, -1
Answer: 100
Step-by-step explanation:
Answer:
3ab
-------------------
(b+a)
Step-by-step explanation:
3/a - 3/b
-------------------
1/a^2 - 1/b^2
Multiply the top and bottom by a^2 b^2/ a^2/b^2 to clear the fractions
(3/a - 3/b) a^2 b^2
-------------------
(1/a^2 - 1/b^2) a^2b^2
3ab^2 - 3 a^2 b
-------------------
b^2 - a^2
Factor out 3ab on the top
3ab( b-a)
-------------------
b^2 - a^2
The bottom is the difference of squares
3ab( b-a)
-------------------
(b-a) (b+a)
Cancel like terms from the top and bottom
3ab
-------------------
(b+a)
Answer:
Sandra need to score at least <u>56%</u> in her fifth test so that her average is 80%.
Step-by-step explanation:
Given:
First 4 test scores = 87%, 92%, 76%,89%
Average targeted = 80%
We need to find the minimum score she needs to make on fifth test to achieve average of at least 80%.
Solution:
Let the minimum score she needs to make in fifth test be 'x'.
Total number of test = 5
Now we know that;
Average is equal to sum of all the scores in the test divided by number of test.
framing in equation form we get;
Multiplying both side by 5 we get;
Subtracting both side by 344 we get;
Hence Sandra need to score at least <u>56%</u> in her fifth test so that her average is 80%.
