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2 years ago

Answer these questions

Mathematics

1 answer:

fgiga [73]2 years ago

5 0

Answer:

y = 5

Step-by-step explanation:

first you subtract 5y from itself and from 7y

then you'll get: 2y + 2 < 12

then subtract the 2 from itself and from the 12

that will give you: 2y < 10

then just divide the 2 from itself and that eliminates the 2 but keeps the y, and divide the 10 by the 2

that'll give you y = 5

You might be interested in

Rico and his friend eat some lasagna. Rico eats 1/9 of lasagna, and his friend eats 1/18 of the lasagna. How much of the lasagna

Blizzard [7]

Answer:

$\frac{5}{6}$ of the lasagna is left

<u>Step-by-step explanation:</u>

Given:

Amount of lasagna Rico eats = 1/9

Amount of lasagna His friend eats = 1/18

To Find:

The amount lasagna is left =?

Solution:

Total lasagna ate by both Rico and his friend = Amount of lasagna Rico eats + Amount of lasagna His friend eats

Total lasagna ate by both Rico and his friend = $\frac{1}{9} + \frac{1}{18}$

Total lasagna ate by both Rico and his friend = $\frac{2}{19} + \frac{1}{18}$

Total lasagna ate by both Rico and his friend = $\frac{3}{18}$

Total lasagna ate by both Rico and his friend = $\frac{1}{6}$

The amount lasagna is left = 1 - Total lasagna ate by both Rico and his friend.

The amount lasagna is left = $1 - \frac{1}{6}$

The amount lasagna is left = $\frac{6-1}{6}$

The amount lasagna is left = $\frac{5}{6}$

4 0

3 years ago

The U.S. Census Bureau conducts a study to determine the time needed to complete the short form. The Bureau surveys 200 people.

NISA [10]

Answer:

$8.2-2.58\frac{2.2}{\sqrt{18}}=6.86$

$8.2+2.58\frac{2.2}{\sqrt{18}}=9.54$

So on this case the 90% confidence interval would be given by (6.86;9.54) And the error is given by:

$ME= 2.58\frac{2.2}{\sqrt{18}} =1.338$

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".

$\bar X=8.2$ represent the sample mean for the sample

$\mu$ population mean (variable of interest)

$\sigma=2.2$ represent the population standard deviation

n represent the sample size

Solution to the problem

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

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

Since the Confidence is 0.90 or 90%, the value of $\alpha=0.1$ and $\alpha/2 =0.005$ , and we can use excel, a calculator or a table to find the critical value. The excel command would be: "=-NORM.INV(0.005,0,1)".And we see that $z_{\alpha/2}=2.58$