If you would like to solve 1/4 * 4/7, you can do this using the following steps:
<span>1/4 * 4/7 = (1 * 4) / (4 * 7) = 4/28 = 1/7
</span>
The correct result would be 1/7.
Answer:
(2, 1)
Step-by-step explanation:
The best way to do this to avoid tedious fractions is to use the addition method (sometimes called the elimination method). We will work to eliminate one of the variables. Since the y values are smaller, let's work to get rid of those. That means we have to have a positive and a negative of the same number so they cancel each other out. We have a 2y and a 3y. The LCM of those numbers is 6, so we will multiply the first equation by a 3 and the second one by a 2. BUT they have to cancel out, so one of those multipliers will have to be negative. I made the 2 negative. Multiplying in the 3 and the -2:
3(-9x + 2y = -16)--> -27x + 6y = -48
-2(19x + 3y = 41)--> -38x - 6y = -82
Now you can see that the 6y and the -6y cancel each other out, leaving us to do the addition of what's left:
-65x = -130 so
x = 2
Now we will go back to either one of the original equations and sub in a 2 for x to solve for y:
19(2) + 3y = 41 so
38 + 3y = 41 and
3y = 3. Therefore,
y = 1
The solution set then is (2, 1)
Answer:
80.0456<
<81.1210
Step-by-step explanation:
-Given the mean, 
and 
, the confidence interval can be calculated using the formula:
#We substitute our values in the formula to solve for CI:
![=\bar x\pm z\times \frac{\sigma}{\sqrt{n}}\\\\=\bar y\pm z_{0.05}\times \frac{s}{\sqrt{72}}\\\\=80.5833\pm 1.645\times \frac{2.77369}{\sqrt{72}}\\\\=80.5833\pm0.5377\\\\=[80.0456,81.1210]](https://tex.z-dn.net/?f=%3D%5Cbar%20x%5Cpm%20z%5Ctimes%20%5Cfrac%7B%5Csigma%7D%7B%5Csqrt%7Bn%7D%7D%5C%5C%5C%5C%3D%5Cbar%20y%5Cpm%20z_%7B0.05%7D%5Ctimes%20%5Cfrac%7Bs%7D%7B%5Csqrt%7B72%7D%7D%5C%5C%5C%5C%3D80.5833%5Cpm%201.645%5Ctimes%20%5Cfrac%7B2.77369%7D%7B%5Csqrt%7B72%7D%7D%5C%5C%5C%5C%3D80.5833%5Cpm0.5377%5C%5C%5C%5C%3D%5B80.0456%2C81.1210%5D)
Hence, the confidence interval lies between 80.0456 and 81.1210
Answer:
okay these problems be changing way too quickly
