Answer: D. 12 ft
Step-by-step explanation:
The inequality would be in the direction of the arrow
The arrow is <—— so the inequality is <
The circle is colored so -3 in including making it less than or equal
x<-3
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Or B
X= -530
This is because:
2(x+60)+2(30)=200
•distribute the 2s into each parentheses
2x+1200+60=200
•combine like-terms
2x+1260=200
•isolate 2x by subtracting 1260 from both sides of the equation
2x=200-1260
•subtract 1260 from 200
2x= -1260
•divide both sides by 2 so you can have x all alone
2x/2= -1260/2
Hence
x= -530
You should use a T distribution to find the critical T value based on the level of confidence. The confidence level is often given to you directly. If not, then look for the significance level alpha and compute C = 1-alpha to get the confidence level. For instance, alpha = 0.05 means C = 1-0.05 = 0.95 = 95% confidence
Use either a table or a calculator to find the critical T value. When you find the critical value, assign it to the variable t.
Next, you'll compute the differences of each pair of values. Form a new column to keep everything organized. Sum everything in this new column to get the sum of the differences, which then you'll divide that by the sample size n to get the mean of the differences. Call this dbar (combination of d and xbar)
After that, you'll need the standard deviation of the differences. I recommend using a calculator to quickly find this. A spreadsheet program is also handy as well. Let sd be the standard deviation of the differences
The confidence interval is in the form (L, U)
L = lower bound
L = dbar - t*sd/sqrt(n)
U = upper bound
U = dbar + t*sd/sqrt(n)