All categories

3 years ago

Find average rate of change f(x)=x^(2)-3x-4 ; [-1,3]

1 answer:

3 0

$\bf slope = m = \cfrac{rise}{run} \implies \cfrac{ f(x_2) - f(x_1)}{ x_2 - x_1}\impliedby \begin{array}{llll} average~rate\\ of~change \end{array}\\\\[-0.35em] \rule{34em}{0.25pt}\\\\ f(x)= x^2-3x-4\qquad \begin{cases} x_1=-1\\ x_2=3 \end{cases}\implies \cfrac{f(3)-f(-1)}{3-(-1)} \\\\\\ \cfrac{[(3)^2-3(3)-4]~~-~~[(-1)^2-3(-1)-4]}{3+1} \\\\\\ \cfrac{[-4]~~-~~[1+3-4]}{4}\implies \cfrac{[-4]-[0]}{4}\implies -1$

You might be interested in

Math question down below

valina [46]

Answer: E. 2/3

Step-by-step explanation:

Division is the same thing as fractions. So 2 divided by 3 is the same thing as 2/3

5 0

3 years ago

Read 2 more answers

In a random sample of cars driven at low altitudes, of them exceeded a standard of grams of particulate pollution per gallon of

Orlov [11]

Complete question is;

In a random sample of 370 cars driven at low altitudes, 43 of them exceeded a standard of 10 grams of particulate pollution per gallon of fuel consumed. In an independent random sample of 80 cars driven at high altitudes, 23 of them exceeded the standard. Can you conclude that the proportion of high-altitude vehicles exceeding the standard is greater than the proportion of low-altitude vehicles exceeding the standard at an level of significance? Group of answer choices

Answer:

Yes we can conclude that there is enough evidence to support the claim that the proportion of high-altitude vehicles exceeding the standard is greater than the proportion of low-altitude vehicles exceeding the standard (P-value = 0.00005).

Step-by-step explanation:

This is a hypothesis test for the difference between the proportions.

The claim is that the proportion of high-altitude vehicles exceeding the standard is greater than the proportion of low-altitude vehicles exceeding the standard.

Then, the null and alternative hypothesis are:

H0 ; π1 - π2 = 0

H1 ; π1 - π2 < 0

The significance level would be established in 0.01.

The random sample 1 (low altitudes), of size n1 = 370 has a proportion of;

p1 = x1/n1

p1 = 43/370

p1 = 0.116

The random sample 2 (high altitudes), of size n2 = 80 has a proportion of;

p2 = x2/n2

p2 = 23/80

p2 = 0.288

The difference between proportions is pd = (p1-p2);

pd = p1 - p2 = 0.116 - 0.288

pd = -0.171

The pooled proportion, we need to calculate the standard error, is:

p = (x1 + x2)/(n1 + n2)

p = (43 + 23)/(370 + 80)

p = 66/450

p = 0.147

The estimated standard error of the difference between means is computed using the formula:

S_(p1-p2) = √[((p(1 - p)/n1) + ((p(1 - p)/n2)]

1 - p = 1 - 0.147 = 0.853

Thus;

S_(p1-p2) = √[((0.147 × 0.853)/370) + ((0.147 × 0.853)/80)]

S_(p1-p2) = 0.044

Now, we can use the formula for z-statistics as;

z = (pd - (π1 - π2))/S_(p1-p2)

z = (-0.171 - 0)/0.044

z = -3.89

Using z-distribution table, we have the p-value = 0.00005

Since the P-value of (0.00005) is smaller than the significance level (0.01), then the effect is significant.

We conclude that The null hypothesis is rejected.

Thus, there is enough evidence to support the claim that the proportion of high-altitude vehicles exceeding the standard is greater than the proportion of low-altitude vehicles exceeding the standard.

6 0

2 years ago

Assume that the readings on the thermometers are normally distributed with a mean of 0 degrees and standard deviation of 1.00deg

IrinaVladis [17]

Answer:

Step-by-step explanation:

Hello!

The variable of interest is the readings on thermometers. This variable is normally distributed with mean μ= 0 degrees C and standard deviation σ= 1.00 degrees C.

The objective is to find the readings that are in the top 3.3% of the distribution and the lowest 3.3% of the distribution.

Symbolically:

The lower value P(X≤a)=0.033

Top value P(X≥b)=0.033

(see attachment)

Lower value:

The accumulated probability until "a" is 0.03, since the variable has a normal distribution, to reach the value of temperature that has the lowest 3.3%, you have to work under the standard normal distribution.

First we look the Z value corresponding to 0.033 of probability:

Z= -1.838

Now you reverste the standardization using the formula Z= (a-μ)/δ

a= (Z*δ)+μ

a= (-1.838*1)+0

a= -1.838

Top value:

P(X≥b)=0.033

This value has 0.033 of the distribution above it then 1 - 0.033= 0.967

is below it.

You can rewrite the expression as:

P(X≤b)=0.967

Now you have to look the value of Z that corresponds to 0.967 of accumulated probability:

b= (Z*δ)+μ

b= (1.838*1)+0

b= 1.838

The cutoff values that separates rejected thermometers from the others are -1.838 and 1.838 degrees C.

I hope it helps!

5 0

2 years ago

35/50 into percentage

lara [203]

35/50 as a percentage is 70%!

6 0

3 years ago

A rally car race course covers 515.97 miles. The winning car completed the course in 6.5 hours. What was the average speed of th

evablogger [386]

Answer:

79.38 miles per hour

Step-by-step explanation:

average speed = miles covered / hours

= 515.97 / 6.5

= 79.38

4 0

3 years ago

Read 2 more answers