X+y+z=2 5x+5y+5z=3 4x+y-3z=-6

Mathematics

1 answer:

aniked [119]2 years ago

5 0

Answer:

Step-by-step explanation:

Examples: 1+2, 1/3+1/4, 2^3 * 2^2

(x+1)(x+2) (Simplify Example), 2x^2+2y a x=5, y=3 (Evaluate Example)

y=x^2+1 (Graph Example), 4x+2=2(x+6) (Solve Example)

You might be interested in

Is 10.846 an integer

yulyashka [42]

Hello!

An integer is defined as a number which is not a fraction or irrational. It should be able to be written out as just a number, without a decimal point or additional fraction. (It can have a negative sign) For example, a few integers would be 2, 5, -8, and 9109, while some non-integers would be 3.1, 3 3/2, and 5i.

In this case, 10.846 is not an integer, as it has a decimal.

Hope this helps!

3 0

2 years ago

A random sample of the costs of repair jobs at a large muffler repair shop produces a mean of $127.95. and a standard deviation

lubasha [3.4K]

Answer:

$127.95-1.685\frac{24.03}{\sqrt{40}}=121.55$

$127.95 +1.685\frac{24.03}{\sqrt{40}}=134.35$

So on this case the 90% confidence interval would be given by (121.55;134.35)

Step-by-step explanation:

Previous concepts

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".

The margin of error is the range of values below and above the sample statistic in a confidence interval.

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

$\bar X=127.95$ represent the sample mean for the sample

$\mu$ population mean (variable of interest)

s=24.03 represent the sample standard deviation

n represent the sample size

Solution to the problem

The confidence interval for the mean is given by the following formula:

$\bar X \pm t_{\alpha/2}\frac{s}{\sqrt{n}}$ (1)

In order to calculate the critical value $t_{\alpha/2}$ we need to find first the degrees of freedom, given by:

$df=n-1=40-1=39$

Since the Confidence is 0.90 or 90%, the value of $\alpha=0.1$ and $\alpha/2 =0.05$ , and we can use excel, a calculator or a table to find the critical value. The excel command would be: "=-T.INV(0.05,39)".And we see that $t_{\alpha/2}=1.685$