If 2a+ 2/a =4, what is the value of 2a^2+ 2/a^2 ?

On Thursday a local shop sold a combination of 417 hamburgers and cheese burgers. The number of cheeseburgers sold was two times

seropon [69]

Answer:

The number of hamburgers sold was 139 and the number of cheeseburgers sold was 278.

Step-by-step explanation:

Let

x -----> the numbers of hamburgers sold on Thursday

y -----> the numbers of cheeseburgers sold on Thursday

we know that

$x+y=417$ ----> equation A

$y=2x$ ----> equation B

Substitute the equation B in equation A and solve for x

$x+2x=417$

$3x=417$

$x=139$

Find the value of y

$y=2(139)=278$

therefore

The number of hamburgers sold was 139 and the number of cheeseburgers sold was 278.

8 0

3 years ago

Carmen spent $18 on fruit at the grocery store. She spent a total of $45 at the store. What percentage of the total did she spen

gladu [14]

All we have to do is divide the money she spent on fruit by the total and multiply that by 100.
18÷45
.4×100
40
So, Carmen spent 40% of her money on fruit.

6 0

4 years ago

A ball is thrown into the air with an upward velocity of 48 ft/s. Its height h in feet after t seconds is given by the function

Masja [62]

The equation modeling the height of the ball at time,t is given by h=-16t²+48t+6
a. In how many seconds does the ball reach its maximum height?
Time taken for the ball to reach the maximum height will be given by:
h'(t)=-32t+48=0
finding the value of t we get:
32t=48
t=48/32
t=1.5 seconds
Thus the time taken for the ball to reach the maximum time is 1.5 seconds

b] What is the ball’s maximum height?
The maximum height will be:
h(1.5)=-16(1.5)²+48(1.5)+6
h(1.5)=42 fee

3 0

3 years ago

A sample of 900900 computer chips revealed that 76v% of the chips do not fail in the first 10001000 hours of their use. The comp

Sergio039 [100]

Answer:

Null hypothesis: $p=0.78$

Alternative hypothesis: $p \neq 0.78$

$z=\frac{0.76 -0.78}{\sqrt{\frac{0.78(1-0.78)}{900}}}=-1.448$

$p_v =2*P(Z$

So the p value obtained was a very high value and using the significance level given $\alpha=0.05$ we see that $p_v>\alpha$ so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, and we can said that at 5% of significance the proportion of chip that do not fail in the first 1000 hours is not significantly different from 0.78 or 78%.

Step-by-step explanation:

1) Data given and notation

n=900 represent the random sample taken

$\hat p=0.76$ estimated proportion of chips do not fail in the first 1000 hours

$p_o=0.78$ is the value that we want to test

$\alpha$ represent the significance level

z would represent the statistic (variable of interest)

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

2) Concepts and formulas to use

We need to conduct a hypothesis in order to test the claim that the true proportion is 0.78:

Null hypothesis: $p=0.78$

Alternative hypothesis: $p \neq 0.78$

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 $p_o$ .

3) Calculate the statistic

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

$z=\frac{0.76 -0.78}{\sqrt{\frac{0.78(1-0.78)}{900}}}=-1.448$

4) Statistical decision

It's important to refresh the p value method or p value approach . "This method is about determining "likely" or "unlikely" by determining the probability assuming the null hypothesis were true of observing a more extreme test statistic in the direction of the alternative hypothesis than the one observed". Or in other words is just a method to have an statistical decision to fail to reject or reject the null hypothesis.

The significance level assumed for this case is $\alpha=0.05$ . The next step would be calculate the p value for this test.

Since is a bilateral test the p value would be:

$p_v =2*P(Z$

So the p value obtained was a very high value and using the significance level given $\alpha=0.05$ we see that $p_v>\alpha$ so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, and we can said that at 5% of significance the proportion of chip that do not fail in the first 1000 hours is not significantly different from 0.78 or 78%.

7 0

3 years ago

1) 2x11 = I don’t know how to do this

Fynjy0 [20]

Answer:

22, Twenty Two

Step-by-step explanation:

A good way to look at multiplying 11 is that the number, if it’s under 10, will then be two of that number. For instance, 4 x 11 = 44, 6 x 11 = 66, and so on and so forth.

Hope This Helped!

5 0

3 years ago