Plzzz help me because i need some good grades

Someone lmk what the answer is

Elodia [21]

$f(-7) = -(-7)^2 - 10 \cdot (-7) + 16\\= -49 + 70 + 16\\= 22$

7 0

4 years ago

Find the area of a square with sides of length 3 yard.

Bumek [7]

To calculate the area of a square, just do length×width. In this case, it is 3×3, so the answer should be 9 square yards.

8 0

3 years ago

Mr. Sánchez owns a square field. The side lengths are 0.9 kilometers. There are 1,980 prairie dog burrows in the fields. What is

Simora [160]

The first thing we are going to do is find the area of the field. To do this we are going to use the area of a square formula: $A=s^2$
Were
$A$ is the area in square kilometers
$s$ is one of the sides of the square
We know for our problem that the side lengths of the field are 0.9 kilometers, so $s=0.9$ . Lets replace that value in our formula to find $A$ :
$A=(0.9)^2$
$A=0.81$

Now, to find the population density of the filed, we are going to use the population density formula: $P_{d}= \frac{I}{A}$
where
$P_{d}$ is the population density in <span>in burrows per square kilometer
</span> $I$ is the number of burrows
$A$ is the are of the field
We know that $I=1980$ and $A=0.81$ , so lets replace those values in our formula:
$P_{d}= \frac{1980}{0.81}$
$P_{d}=2444.4$

We can conclude that the <span>density of prairie dog burrows is approximately 2444 burrws per square kilometer.</span>

5 0

3 years ago

Dan earns £342 over the course of a five-day week. How much is that per day?

alex41 [277]

Answer:

68.4

Step-by-step explanation:

Divide 342 by 5

3 0

2 years ago

Read 2 more answers

A film distribution manager calculates that 7% of the films released are flops. If the manager is correct, what is the probabili

diamong [38]

Answer:

0.9909 = 99.09% probability that the proportion of flops in a sample of 404 released films would be greater than 4%

Step-by-step explanation:

I am going to use the binomial approximation to the normal to solve this question.

Binomial probability distribution

Probability of exactly x sucesses on n repeated trials, with p probability.

Can be approximated to a normal distribution, using the expected value and the standard deviation.

The expected value of the binomial distribution is:

$E(X) = np$

The standard deviation of the binomial distribution is:

$\sqrt{V(X)} = \sqrt{np(1-p)}$

Normal probability distribution

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:

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

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.

When we are approximating a binomial distribution to a normal one, we have that $\mu = E(X)$ , $\sigma = \sqrt{V(X)}$ .