Pls help I need a good grade

PLS HELP ME

MrRa [10]

false... even if you got 100 on the next test, you would only have an 84 average

Hope this helped!!! :) (comment if you don't understand)

3 0

3 years ago

Use slopes and y-intercepts to determine if the lines 6x+y=−1 and −2x−5y=1 are parallel.

kobusy [5.1K]

Answer:

The two lines are not parallel.

Step-by-step explanation:

Every linear equation follows this structure:

y = mx + b

y is the y value

x is the x value

m is the gradient/slope of the line

b (or sometimes c) is the y-intercept of the line

Firstly, we have to get the y term on one side by itself.

6x + y = -1

-6x -6x

y = -6x - 1

-2x -5y = 1

+2x +2x

-5y = 2x + 1

Secondly, we make it so the y term is just the y value.

The first equation is already like this, so we don't need to do anything to that.

-5y = 2x + 1

÷ -5 ÷ -5

y = (2x + 1) / -5

This can be expanded and simplified to:

y = -2/5x - 1/5

Thirdly, we have to compare the slopes and y-intercepts.

y = -6x - 1

y = 2/5x - 1/5

If the slopes are the same and the y-intercepts are different, they are parallel. However, the slopes are different, therefore they are not parallel.

7 0

3 years ago

A manufacturer of nickel-hydrogen batteries randomly selects 100 nickel plates for test cells, cycles them a specified number of

kolezko [41]

Answer:

a) Parameter of interest $p$ representing the true proportion of the plates have blistered.

b) Null hypothesis: $p\leq 0.1$

Alternative hypothesis: $p > 0.1$

c) $z=\frac{0.14 -0.1}{\sqrt{\frac{0.1(1-0.1)}{100}}}=1.33$

d) For this case we need to find a value in the normal standard distribution that accumulates 0.1 of the area in the right tail and for this case is:

$z_{critc}= 1.28$

e) For this case since our calculated value is higher than the critical value 1.33>1.28 we have enough evidence to reject the null hypothesis and we can conclude that the true proportion is significantly higher than 0.1

f) $p_v =P(z>1.33)=0.0917$

If we compare the p value and the significance level given $\alpha=0.1$ we see that $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis, and we can said that at 10% of significance the true proportion is higher than 0.1 or 10%

Step-by-step explanation:

Data given and notation

n=100 represent the random sample taken

Part a

Parameter of interest $p$ representing the true proportion of the plates have blistered.

X=14 represent the number of the plates have blistered.

$\hat p=\frac{14}{100}=0.14$ estimated proportion of the plates have blistered.

$p_o=0.1$ is the value that we want to test

$\alpha=0.1$ represent the significance level

Confidence=90% or 0.90

z would represent the statistic (variable of interest)

$p_v$ represent the p value (variable of interest)

Part b: Concepts and formulas to use

We need to conduct a hypothesis in order to test the claim that more than 10% of all plates blister under such circumstances.:

Null hypothesis: $p\leq 0.1$

Alternative hypothesis: $p > 0.1$

When we conduct a proportion test we need to use the z statistic, and the is given by:

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

The One-Sample Proportion Test is used to assess whether a population proportion $\hat p$ is significantly different from a hypothesized value $p_o$ .

Part c: Calculate the statistic

Since we have all the info requires we can replace in formula (1) like this:

$z=\frac{0.14 -0.1}{\sqrt{\frac{0.1(1-0.1)}{100}}}=1.33$

Part d: Rejection region

For this case we need to find a value in the normal standard distribution that accumulates 0.1 of the area in the right tail and for this case is:

$z_{critc}= 1.28$

Part e

For this case since our calculated value is higher than the critical value 1.33>1.28 we have enough evidence to reject the null hypothesis and we can conclude that the true proportion is significantly higher than 0.1

Part f

Since is a right taild test the p value would be:

$p_v =P(z>1.33)=0.0917$

If we compare the p value and the significance level given $\alpha=0.1$ we see that $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis, and we can said that at 10% of significance the true proportion is higher than 0.1 or 10%

7 0

3 years ago

Ten weight lifters are competing in a team weight-lifting contest. Of the lifters, 3 are from the United States, 4 are from Russ

ruslelena [56]

Answer:

(a) 65536 - the basic principle of counting

(b) 2520 - use the multinomials.

Step-by-step explanation:

Divide 8 people among 4 schools

The teachers are different among themselves, and so are the schools.

(a)

Every teacher can choose a school. By the basic principle of counting: 4.4.4.4.4.4.4.4 = 4^8 = 65536

different divisions of the teachers

Note: this does not ensure that every school gets a teacher

(b) - <u>Every school gets precisely 2 teachers:</u>

to divide 8 different objects into four groups of fixed sizes 2, 2, 2 and 2, use the multinomial coefficient

( 8 2, 2, 2, 2) = (8!)/(2!2!2!2!) ==> 2520

different divisions of the teachers

5 0

3 years ago

The winner of a golf tournament made five putts for birdies. The lengths of these putts are in the table shown. What is the tota

Elden [556K]

First, note that

1 yard = 3 foot,

1 feet = 12 inches.

Now add all lengths:

15 ft 4 in + 9 ft 2 in + 14 ft 7 in + 10 ft 11 in +5 ft 8 in = 53 ft 32 in.

Since 32 in = 24 in + 8 in = 2 ft 8 in, then

53 ft 32 in = 53 ft + 2 ft 8 in =55 ft 8 in.

Since 55 ft = 54 ft + 1 ft = 18 yd 1 ft, then

55 ft 8 in = 18 yd 1 ft 8 in.

Answer: correct choice C

3 0

4 years ago