Answer:
0.360 % or 40%
Step-by-step explanation:
Area circle = 50.27 (50)
Area square = 32.3 (32)
Area circle minus area square = 50.27-32.3= 17.97 (18)
18/50 = 9/25 = 0.36
Answer:
x = -3/2
Step-by-step explanation:
4x² + 12x + 9 = 0
Use AC method to factor, or recognize the perfect square.
(2x + 3)² = 0
2x + 3 = 0
x = -3/2
Answer:
A sample of 179 is needed.
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 .
That is z with a pvalue of , so Z = 1.44.
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.
A previous study found that for an average family the variance is 1.69 gallon?
This means that
If they are using a 85% level of confidence, how large of a sample is required to estimate the mean usage of water?
A sample of n is needed, and n is found for M = 0.14. So
Rounding up
A sample of 179 is needed.
Consider expression First, you can factor it:
Since x is integer number, then you can see that x-1 is previous integer number (x-1 is 1 unit smaller than x).
Therefore, x-1 and x are two consecutive integers. When you have two consecutive integers, one of them is always even and one is always odd. Multiplying even integer number by odd integer number you always get even integer number.
Thus, is always even.