A function is shown in the table below. What equation represents this function?

Which exponential function is represented by the values in the table?

Goryan [66]

Answer:

$\displaystyle f(x)=4\cdot\left(\frac{1}{2}\right)^x$

Step-by-step explanation:

<u>Exponential Function</u>

The exponential function can be written with the general equation:

$f(x)=A\cdot r^x$

Where A is the value when x=0 and r>0 is the ratio. If r is greater than 1, the function is increasing, if r is less than 1, the function is decreasing.

The table shows the relation between values of x and values of the function y. Note that as x increases (one by one), y decreases with a ratio of 1/2. Only the last two choices have ratios of r=1/2. We only have to test which one of them has the correct value of y=4 when x=0.

Substituting in the third function:

$\displaystyle f(x)=4\cdot\left(\frac{1}{2}\right)^x$

$\displaystyle f(0)=4\cdot\left(\frac{1}{2}\right)^0$

$f(0) = 4$

This gives the correct value of f(0)=4.

Substituting in the fourth function:

$\displaystyle f(x)=\frac{1}{2}\cdot\left(\frac{1}{2}\right)^x$

$\displaystyle f(0)=\frac{1}{2}\cdot\left(\frac{1}{2}\right)^0$

$f(0) = \frac{1}{2}$

This choice is wrong

Correct choice:

$\boxed{\displaystyle f(x)=4\cdot\left(\frac{1}{2}\right)^x}$

8 0

3 years ago

Can someone help me with this problem

nikdorinn [45]

Answer: x = 33°

Step-by-step explanation: A triangle's angles should all equal 180, so we can set up an equation to help us.

106 + 41 + x = 180

Add 106 and 41

147 + x = 180

Subtract 147 on both sides.

x = 33

And there you go :)

5 0

3 years ago

The time a randomly selected individual waits for an elevator in an office building has a uniform distribution with a mean of 0.

Amiraneli [1.4K]

Answer:

The mean of the sampling distribution of means for SRS of size 50 is $\mu = 0.5$ and the standard deviation is $s = 0.0409$

By the Central Limit Theorem, since we have of sample of 50, which is larger than 30, it does not matter that the underlying population distribution is not normal.

0% probability a sample of 50 people will wait longer than 45 seconds for an elevator.

Step-by-step explanation:

To solve this problem, we need to understand the normal probability distribution and the central limit theorem.

Normal probability distribution:

Problems of normally distributed samples are 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:

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

The Z-score measures how many standard deviations the measure is from the mean. 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, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

Central limit theorem:

The Central Limit Theorem estabilishes that, for a random variable X, with mean $\mu$ and standard deviation $\sigma$ , a large sample size, of at least 30, can be approximated to a normal distribution with mean $\mu$ and standard deviation $s = \frac{\sigma}{\sqrt{n}}$

In this problem, we have that:

$\mu = 0.5, \sigma = 0.289$

What are the mean and standard deviation of the sampling distribution of means for SRS of size 50?

By the Central Limit Theorem

$\mu = 0.5, s = \frac{0.289}{\sqrt{50}} = 0.0409$

The mean of the sampling distribution of means for SRS of size 50 is $\mu = 0.5$ and the standard deviation is $s = 0.0409$

Does it matter that the underlying population distribution is not normal?

By the Central Limit Theorem, since we have of sample of 50, which is larger than 30, it does not matter that the underlying population distribution is not normal.

What is the probability a sample of 50 people will wait longer than 45 seconds for an elevator?

We have to use 45 seconds as minutes, since the mean and the standard deviation are in minutes.

Each minute has 60 seconds.

So 45 seconds is 45/60 = 0.75 min.

This probability is 1 subtracted by the pvalue of Z when X = 0.75. So

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

By the Central Limit Theorem

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

$Z = \frac{0.75 - 0.5}{0.0409}$

$Z = 6.11$

$Z = 6.11$ has a pvalue of 1

1-1 = 0

0% probability a sample of 50 people will wait longer than 45 seconds for an elevator.

8 0

3 years ago

Calculate the value of each of the following

Ghella [55]

Answer:

104.7664068

Step-by-step explanation:

5 0

2 years ago

3. Six less than twice a number is 17. Which equation could be used to determine the

Usimov [2.4K]

Answer & Step-by-step explanation:

n represents our number. So, twice a number would be 2n because twice means multiply by two.

When the problem says 6 less, then it means 6 less than 2n. So, it would look like 2n-6.

FInally, the problem says that all of this equals 17 so 17 would be the result.

So, you answer is 2n-6 = 17. This is answer choice B.

6 0

3 years ago