Which exponential function has an x-intercept?

The size of fish is very important to commercial fishing. A study conducted in 2012 found the length of Atlantic cod caught in n

devlian [24]

Answer:

The length of the longest 15% of Atlantic cod in this area is 53.79cm, roundeed to 2 decimal places.

Step-by-step explanation:

Problems of normally distributed samples can be solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by

$Z = \frac{X - \mu}{\sigma}$

After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X.

In this problem, we have that:

A study conducted in 2012 found the length of Atlantic cod caught in nets in Karlskrona to have a mean of 49.9 cm and a standard deviation of 3.74 cm, so $\mu = 49.9, \sigma = 3.74$ .

What is the length in cm of the longest 15% of Atlantic cod in this area?

We have to find the value of X for the value of Z that has a pvalue of 0.85.

Looking at the zscore table, we have that Z = 1.04 has a pvalue of 0.8508. So, we have to find the value of X when $Z = 1.04, \mu = 49.9, \sigma = 3.74$ .

So

$Z = \frac{X - \mu}{\sigma}$

$1.04 = \frac{X - 49.9}{3.74}$

$X - 49.9 = 3.8896$

$X = 53.7896$

The length of the longest 15% of Atlantic cod in this area is 53.79cm, roundeed to 2 decimal places.

8 0

2 years ago

A newsletter publisher believes that 55% of their readers own a Rolls Royce. Is there sufficient evidence at the 0.05 level to r

melomori [17]

Set up hypotheses:

The null hypotheses is that the proportion of readers who own a Rolls Royce is equal to 0.55

Null hypotheses = H₀: p = 0.55

The alternate hypotheses is that the proportion of readers who own a Rolls Royce is not equal to 0.55

Alternate hypotheses = H₁: p ≠ 0.55

Determine the type of test:

Since the alternate hypothesis states that the proportion of readers who own a Rolls Royce is different, therefore it is a two-tailed test.

Determine the level of significance and Critical Z-score:

Given level of significance = 0.05

Since it is a two-tailed test,

Z-score = 1.960 (two tailed)

Set up decision rule:

Since it is a two-tailed test, using a Z statistic at a significance level of 5%

We Reject H₀ if Z < -1.960 or Z > 1.960

We Reject H₀ if p ≤ α

Compute the test statistic:

The test statistic may be calculated using,

$Z = \frac{\hat{p} - p}{ \sqrt{\frac{p(1-p)}{n} }}$

We are not given enough information to find out the test statistic.

Conclusion:

We do not have enough information to accept or refuse the publisher's claim.

4 0

2 years ago

If AD=20 and AC=3x+4, find the value of x. Then find AC and DC.<br><br> I don't understand.

Fofino [41]

<span>Using the information we have 3x+4=40 Do the same to each side of the equation to eliminate for x. 3x+4=40 Minus 4 from each side 3x=40-4 3x=36 Divide 3 from each side x=36/3 x=12 AC=3x+4 insert the value of x 3(12)+4=40 AC=40 AD=20</span>

5 0

2 years ago

The owner of a chain of supermarkets notices that there is a positive correlation between the sales of beer and the sales of ice

Dmitry_Shevchenko [17]

Answer:

D. the sale of beer and ice cream may both be affected by another variable such as the outside temperature.

Step-by-step explanation:

A. There is no evidence to indicate that the positive correlation observed is an error.

B. Even though there is a positive correlation between beer and ice cream sales, there is no evident cause and consequence relationship.

C. The relationship isn't necessarily linear.

D. It is plausible to assume that the sales of beer and ice cream are both affected by another variable like temperature. Both of the products are usually consumed cold and should see an increase in sales during warmer seasons and a decrease in sales during colder seasons.

4 0

2 years ago

Four men are to divide K500 equally among them. When the money was given, 20% was taken away.

Agata [3.3K]

Answer: 20% of 500= 100

So 500-100 = 400

4x100= 400

Step-by-step explanation:

4 0

2 years ago