Solve the inequality 16 – 7a ≥

Given that Jocelyn saved $60 in 8 weeks, predict the number of weeks it will take Jocelyn to save $90. Include in your explanati

SashulF [63]

number of weeks: <em>w </em>is the x value, and the number of money saved: <em>m</em> is the y value. First, we need to find out how much she makes in 1 <em>w </em>and because k = y/x, we need to divide 60 by 8, which gives u 7.5, so she saves $7.50 every week Finally, we figure out the number of weeks it takes her to save $90, and to do that, we use the formula x = y/k. Using that formula, we get the expression $90/$7.50 or $90/$7.5. 90/7.50 = 12, so x = 12. It will take her 12 weeks to save $90. In order to check our answer, we can say that we didn't know the number of <em>m</em> she saved, but we do know how many weeks. To find a solution, we use the formula y = kx (the blank between kx means that we are multiplying). Using that formula, we get the equation 12 X 7.50. When we solve this equation, we get 90, and since it is the same answer as the real problem, that means the answer for the real problem is correct. (BTW sorry this is so long)

8 0

3 years ago

Suppose we are interested in analyzing the weights of NFL players. We know that on average, NFL players weigh 247 pounds with a

tigry1 [53]

Answer:

$SE= \frac{\sigma}{\sqrt{n}} = \frac{47}{\sqrt{30}}= 8.58$

$ME= 1.64 *\frac{\sigma}{\sqrt{n}} = 1.64*\frac{47}{\sqrt{30}}= 14.073$

$\bar X - ME = 237- 14.073 = 222.927$

$\bar X + ME = 237+ 14.073 = 251.073$

$n=(\frac{1.640(47)}{5})^2 =237.65 \approx 238$

So the answer for this case would be n=238 rounded up to the nearest integer

Null hypothesis: $\mu \geq 247$

Alternative hypothesis: $\mu$

$z=\frac{237-247}{\frac{47}{\sqrt{30}}}=-1.165$

$p_v =P(z$

If we compare the p value and the significance level given $\alpha=0.1$ we see that $p_v>\alpha$ so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, and we can't conclude that the true mean is lower than 247 at 10% of significance.

Step-by-step explanation:

For this case we have the following data given:

$\bar X =237$ represent the sample mean

$\sigma = 47$ represent the population deviation

$n =30$ represent the sample size selected

$\mu_0 = 247$ represent the value that we want to test.

The standard error for this case is given by:

$SE= \frac{\sigma}{\sqrt{n}} = \frac{47}{\sqrt{30}}= 8.58$

For the 90% confidence the value of the significance is given by $\alpha=1-0.9 = 0.1$ and $\alpha/2 = 0.05$ so we can find in the normal standard distribution a quantile that accumulates 0.05 of the area on each tail and we got:

$z_{\alpha/2}= 1.64$

And the margin of error would be:

$ME= 1.64 *\frac{\sigma}{\sqrt{n}} = 1.64*\frac{47}{\sqrt{30}}= 14.073$

The confidence interval for this case would be given by:

$\bar X - ME = 237- 14.073 = 222.927$

$\bar X + ME = 237+ 14.073 = 251.073$

The margin of error is given by this formula:

$ME=z_{\alpha/2}\frac{\sigma}{\sqrt{n}}$ (a)

And on this case we have that ME =5 and we are interested in order to find the value of n, if we solve n from equation (a) we got:

$n=(\frac{z_{\alpha/2} \sigma}{ME})^2$ (b)

Replacing into formula (b) we got:

$n=(\frac{1.640(47)}{5})^2 =237.65 \approx 238$

So the answer for this case would be n=238 rounded up to the nearest integer

State the null and alternative hypotheses.

We need to conduct a hypothesis in order to check if the true mean is lower than 247 pounds, the system of hypothesis would be:

Null hypothesis: $\mu \geq 247$

Alternative hypothesis: $\mu$

Since we know the population deviation, is better apply a z test to compare the actual mean to the reference value, and the statistic is given by:

$z=\frac{\bar X-\mu_o}{\frac{\sigma}{\sqrt{n}}}$ (1)

z-test: "Is used to compare group means. Is one of the most common tests and is used to determine if the mean is (higher, less or not equal) to an specified value".

Calculate the statistic

We can replace in formula (1) the info given like this:

$z=\frac{237-247}{\frac{47}{\sqrt{30}}}=-1.165$

P-value

Since is a left tailed test the p value would be:

$p_v =P(z$

Conclusion

If we compare the p value and the significance level given $\alpha=0.1$ we see that $p_v>\alpha$ so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, and we can't conclude that the true mean is lower than 247 at 10% of significance.

5 0

3 years ago

What is the equation of a line that passes through the point(0, 3) and has a slope of 2

stealth61 [152]

Answer:

the equation of a line that passes through the point(0,3) answer is 1.5

Step-by-step explanation:

5 0

3 years ago

. The admission fee for a basketball game is $5 for students and $7 for adults. At one of the girl’s home games, 150 people atte

exis [7]

Answer:

Adults =58, Students=92

Step-by-step explanation:

7 0

3 years ago

Find the value of x and y

tiny-mole [99]

x° + 2y° = 180° ⇒ 2y° = 180° - x°

x° = 60° {three sides of the same lengh, means three angles=60°}

2y° = 180° - 60°

2y° = 120°

y° = 60°

4 0

3 years ago

Solve the inequality 16 – 7a ≥ –33.