The first one? i dont know what else itd be
Answer:
7z + 5 + 6z - 9 (Add 7z and 6z, subtract 9 from 5)
<em>13z - 4 </em>(Can't be simplified further)
Answer:
3.83
Step-by-step explanation:
Mean of x = Σx / n
Mean of x = (14 + 19 + 13 + 6 + 9) / 5 = 12.2
Sum of square (SS) :
(14-12.2)^2 + (19-12.2)^2 + (13-12.2)^2 + (6-12.2)^2 + (9-12.2)^2 = 98.8
Mean of y = Σy / n
Mean of y = (101 + 89 + 48 + 21 + 47) / 5 = 61.2
Σ(y - ybar)² = (101-61.2)^2 + (89-61.2)^2 + (48-61.2)^2 + (21-61.2)^2 + (47-61.2)^2 = 4348.8
df = n - 2 = 5 - 2 = 3
Σ(y - ybar)² / df = 4348.8 / 3 = 1449.6
√(Σ(y - ybar)² / df) = √1449.6 = 38.074
Standard Error = √(Σ(y - ybar)² / df) / √SS
Standard Error = 38.074 / √98.8
Standard Error = 3.83
Answer:
2x³ + x² - 11x - 15
Step-by-step explanation:
Step 1: Write out expression
2x³ + x² + 7x - 6 - (-2x + 10x + 10x + 9)
Step 2: Distribute negative
2x³ + x² + 7x - 6 + 2x - 10x - 10x - 9
Step 3: Combine like terms (x)
2x³ + x² + 9x - 10x - 10x - 9 - 6
2x³ + x² - x - 10x - 9 - 6
2x³ + x² - 11x - 9 - 6
Step 4: Combine like terms (constants)
2x³ + x² - 11x - 15
Answer:
538 books should be tested.
Step-by-step explanation:
We have that to find our
level, that is the subtraction of 1 by the confidence interval divided by 2. So:

Now, we have to find z in the Ztable as such z has a pvalue of
.
So it is z with a pvalue of
, so 
Now, find the margin of error M as such

In which
is the standard deviation of the population and n is the size of the sample.
How many books should be tested to estimate the average force required to break the binding to within 0.08 lb with 99% confidence?
n books should be tested.
n is found when 
We have that 






Rounding up
538 books should be tested.