Given:
Current population = x
The population of a city is expected to decrease by 6% next year.
To find:
The expression that represents the expected population next year.
Solution:
We have,
Current population = x
Decrease rate = 6%.
Expected population next year = Current population - 6% of Current population
=
=
=
Therefore, the expression for the expected population next year is 0.94x.
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)
B & C would be your answer because 3^-3 would turn into a fraction, 1/3^3 which is the same as C.
Answer:
x=2 and x=12
Step-by-step explanation:
|2x+1| = |3x-11|
2x+1 = 3x-11
2x = 3x-12
-x = -12
x = 12
2x+1 = -(3x-11)
2x+1 = -3x+11
5x+1 = 11
5x = 10
x = 2
2/3(x + 7) = 10. Divide each side by 2/3.
x + 7 = 15. Subtract each side by 7.
x = 8
