[45-(6+3)]*7=<br> ???????

The cost of Mr. Patten’s car insurance increased by 5% to $86.82 per month. What was the cost of his insurance before it increas

Nostrana [21]

Answer:

Considering is a compunded increase rate of the yearly car insurance fee and x is the initial value of the insurance fee then

x×(1.05)^12=$86.82

×=$86.82/(1.05)^12

7 0

3 years ago

Graph f(x)=−1.5x+6.<br><br> Use the line tool and select two points to graph the line.

aev [14]

Answer: Points (-1 , 7.5), (0 , 6), and (1 , 4.5).

Step-by-step explanation:

7 0

3 years ago

A cube with side length m has a volume of 343 cubic centimeters. The following equation shows the volume of the cube.

Tanzania [10]

To find the side length of a cube with a volume of 343, you need to find m to the third power. Solve that and you get 7. m = 7

8 0

3 years ago

Read 2 more answers

The amount of money spent on textbooks per year for students is approximately normal.

Ostrovityanka [42]

Answer:a

a

$336.04 < \mu < 443.96$

b

The margin of error will increase

c

The margin of error will decreases

d

The 99% confidence interval is $0.4107 < p < 0.4293$

Step-by-step explanation:

From the question we are told that

The sample size $n = 19$

The sample mean is $\= x = \$\ 390$

The standard deviation is $\sigma = \$ \ 120$

Given that the confidence level is 95% then the level of significance is mathematically represented as

$\alpha = 100 - 95$

$\alpha = 5 \%$

$\alpha = 0.05$

Next we obtain the critical value of $\frac{\alpha }{2}$ from the normal distribution table

So

$Z_{\frac{\alpha }{2} } = 1.96$

The margin of error is mathematically represented as

$E = Z_{\frac{\alpha }{2} } * \frac{\sigma}{\sqrt{n} }$

=> $E = 1.96 * \frac{120}{\sqrt{19} }$

=> $E = 53.96$

The 95% confidence interval is

$\= x - E < \mu < \= x + E$

=> $390 - 53.96 < \mu < 390 - 53.96$

=> $336.04 < \mu < 443.96$

When the confidence level increases the $Z_{\frac{\alpha }{2} }$ also increases which increases the margin of error hence the confidence level becomes wider

Generally the sample size mathematically varies with margin of error as follows

$n \ \ \alpha \ \ \frac{1}{E^2 }$

So if the sample size increases the margin of error decrease

The sample proportion is mathematically represented as

$\r p = \frac{210}{500}$

$\r p = 0.42$

Given that the confidence level is 0.99 the level of significance is $\alpha = 0.01$

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

$Z_{\frac{\alpha }{2} } = 2.58$

Generally the margin of error is mathematically represented as

$E = Z_{\frac{\alpha }{2} }* \sqrt{ \frac{\r p (1- \r p )}{n} }$

=> $E = 0.42 * \sqrt{ \frac{0.42 (1- 0.42 )}{ 500} }$

=> $E = 0.0093$

The 99% confidence interval is

$\r p - E < p < \r p + E$

$0.42 - 0.0093 < p < 0.42 + 0.0093$

$0.4107 < p < 0.4293$

4 0

3 years ago

Which best describes the polygon whose vertices in the coordinate plane are (-2,3),(2,3),(2,-1),(-2,-1)

earnstyle [38]

The polygon is a perfect square. I graphed those points on a graph. I hope this helped if not let me know so I can try and write the correct answer.

7 0

3 years ago

[45-(6+3)]*7= ???????