What is the value of x?

You are interested in estimating the the mean age of the citizens living in your community. In order to do this, you plan on con

Naddika [18.5K]

Answer:

The sample size is $n = 68$

Step-by-step explanation:

From the question we are told that

The margin of error is $E = 5 \ years$

The standard deviation is $\sigma = 22$

From the question we are told the confidence level is 94% , hence the level of significance is

$\alpha = (100 - 94 ) \%$

=> $\alpha = 0.06$

Generally from the normal distribution table the critical value of $\frac{\alpha }{2}$ is

$Z_{\frac{\alpha }{2} } = 1.881$

Generally the sample size is mathematically represented as

$n = [\frac{Z_{\frac{\alpha }{2} } * \sigma }{E} ] ^2$

=> $n = [\frac{1.881 } * 22 }{5} ] ^2$

=> $n = 68$

8 0

2 years ago

Math work help wanted

Sidana [21]

Answer:

$\frac{31}{20}\pi$

Step-by-step explanation:

The circumference of circle G is 2pi, which means that HJ is equal to 81/360*2pi = 9pi/20, which means that RJ is equal to 18pi/20-9pi/20 = 9pi/20. Therefore, RHJ is equal to the circumference of the area minus RJ, which is equal to 40pi/20 - 9pi/20 = 31pi/20

I hope this helps

3 0

2 years ago

Please help i will mark brainliest

Evgen [1.6K]

Answer:

2. $\left[\begin{array}{ccc}1&4\\0&3\\\end{array}\right]$

3. $\left[\begin{array}{ccc}-3&21&60\\-15&9&-45\\\end{array}\right]$

4. $\left[\begin{array}{ccc}6&-14\\-2&-6\\\end{array}\right]$

Step-by-step explanation:

2. This matrix is easy, as it just requires addition.

$\left[\begin{array}{ccc}1&4\\0&3\\\end{array}\right]$ + $\left[\begin{array}{ccc}0&0\\0&0\\\end{array}\right]$ = $\left[\begin{array}{ccc}1&4\\0&3\\\end{array}\right]$

3. This matrix requires for the matrices to be multiplied first, then added.

$\left[\begin{array}{ccc}9&-15&18\\-27&15&-9\\\end{array}\right]$ + $\left[\begin{array}{ccc}-12&36&42 \\12& -6 & -36 \\\end{array}\right]$ = $\left[\begin{array}{ccc}-3&21&60\\-15&9&-45\\\end{array}\right]$

4. Here we can add the last 2 matrices to find x.

$\left[\begin{array}{ccc}2&-8\\-4&2\\\end{array}\right]$ + $\left[\begin{array}{ccc}4&-6\\2&-8 \\\end{array}\right]$ = $\left[\begin{array}{ccc}6&-14\\-2&-6\\\end{array}\right]$

Hope this helps! (Please consider giving brainliest)

4 0

3 years ago

A survey of 2500 subscribers to a certain news paper revealed that 2250 people subscribe to the daily morning edition and 1250 s

Aleks04 [339]

1500 people subscribed Sunday edition and 250 people subscribed only sunday edition.

<u>Solution:</u>

Given, A survey of 2500 subscribers to a certain news paper revealed that 2250 people subscribe to the daily morning edition

And 1250 subscribe to both the daily and the sunday editions.

We have to find how many subscribe to the Sunday edition? how many subscribe to the Sunday edition only?

Let x denote the number who subscribe to the Sunday edition.

Then the addition rule with overlap tells us that

Those who subscribe daily edition + those who subscribe sunday edition - those who subscribe both daily and sunday edition = total subscribers in survey

2250 + x – 1250 = 2500

1000 + x = 2500

x = 1500

so, 1500 subscribe to the Sunday edition and 1500 – 1250 = 250 subscribe to the Sunday edition only.

Hence, 1500 people subscribed Sunday edition and 250 people subscribed only sunday edition.

6 0

3 years ago

A cyclist rides at an average speed of 31 miles per hour. The cyclist’s speed, s, can differ from the average by as much as 8 mi

Shalnov [3]

In this compound inequality X should be 8.

4 0

3 years ago

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