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3 years ago

11

At a gas station 84% of the customers buy gasoline. Only 5% of the customers buy gasoline and a beverage. What is the probabilit

y that a customer who buys gasoline also buys a beverage

1 answer:

loris [4]3 years ago

4 0

Wouldn't it just be 5%?

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Using the numbers 3, 4, 5, and 7 create the smallest fraction and the largest fraction.(Please explain the steps)

luda_lava [24]

Answer:

largest: 7/3 smallest: 3/7

Step-by-step explanation:

the answer kinda explains the question on its own, but all it really is, is put largest on the smallest, or put the smallest an the largest.

5 0

3 years ago

26. A book costs sh. (x - 300) and a pen costs sh (x + 100). If Ndagire pad sh. 3300 for 3 books and 2 pens, how much did she pa

saul85 [17]

Answer:

500 and 900

Step-by-step explanation:

3(x - 300) + 2(x + 100) = 3300 ← distribute parenthesis

3x - 900 + 2x + 200 = 3300

5x - 700 = 3300 ( add 700 to both sides )

5x = 4000 ( divide both sides by 5 )

x = 800

Then

cost of book = x - 300 = 800 - 300 = 500

cost of pen = x + 100 = 800 + 100 = 900

7 0

1 year ago

Yaro buys a baseball cap for $9.50. He also buys a new baseball. Yaro speads $13.50 altogether.

VMariaS [17]

Answer:

13.5 = 9.5 + x

x=4

Step-by-step explanation:

In this problem, the price of the baseball cap, which is $9.50, and a baseball, whose price is unknown (and therefore must be the variable), total $13.50. So, to set up the equation add the two prices and set them equal to the total, 9.5+x=13.5.

Then, using the subtraction property of equality subtract 9.5 from both sides. This means x=4, so the baseball cost 4 dollars.

4 0

2 years ago

PLEASE HELP GIVING BRAINLIST!!! Given ΔXYZ is isosceles, what is XZ if the perimeter is 107 units and XZ = 1/2 XY?

Tema [17]

XY+YZ+XZ=107

XY and YZ be x

x+x+1/2x=107
2x+1/2x=107
4x+x/2=107
5x/2=107
5x=214
x=42.8units

6 0

2 years ago

In a recent year, a poll asked 2362 random adult citizens of a large country how they rated economic conditions. In the poll,

Harman [31]

Answer:

a) The 99% confidence interval is given by (0.198;0.242).

b) Based on the p value obtained and using the significance level assumed $\alpha=0.01$ we have $p_v>\alpha$ so we can conclude that we fail to reject the null hypothesis, and we can said that at 1% of significance the proportion of people who are rated with Excellent/Good economy conditions not differs from 0.24. The interval also confirms the conclusion since 0.24 it's inside of the interval calculated.

c) $\alpha=0.01$

Step-by-step explanation:

<em>Data given and notation </em>

n=2362 represent the random sample taken

X represent the people who says that they would watch one of the television shows.

$\hat p=\frac{X}{n}=0.22$ estimated proportion of people rated as Excellent/Good economic conditions.

$p_o=0.24$ 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) <em> </em>

<em>Concepts and formulas to use </em>

We need to conduct a hypothesis in order to test the claim that 24% of people are rated with good economic conditions:

Null hypothesis: $p=0.24$

Alternative hypothesis: $p \neq 0.24$

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 a: Test the hypothesis

<em>Check for the assumptions that he sample must satisfy in order to apply the test </em>

a)The random sample needs to be representative: On this case the problem no mention about it but we can assume it.

b) The sample needs to be large enough

np = 2362x0.22=519.64>10 and n(1-p)=2364*(1-0.22)=1843.92>10

Condition satisfied.

<em>Calculate the statistic</em>

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

$z=\frac{0.22 -0.24}{\sqrt{\frac{0.24(1-0.24)}{2362}}}=-2.28$

The confidence interval would be given by:

$\hat p \pm z_{\alpha/2}\sqrt{\frac{\hat p (1-\hat p)}{n}}$

The critical value using $\alpha=0.01$ and $\alpha/2 =0.005$ would be $z_{\alpha/2}=2.58$ . Replacing the values given we have:

$0.22 - (2.58)\sqrt{\frac{0.22(1-0.22)}{2362}}=0.198$

$0.22 + (2.58)\sqrt{\frac{0.22(1-0.22)}{2362}}=0.242$

So the 99% confidence interval is given by (0.198;0.242).

Part b

<em>Statistical decision </em>

P value method or p value approach . "This method consists on 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 provided is $\alpha=0.01$ . 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 based on the p value obtained and using the significance level assumed $\alpha=0.01$ we have $p_v>\alpha$ so we can conclude that we fail to reject the null hypothesis, and we can said that at 1% of significance the proportion of people who are rated with Excellent/Good economy conditions not differs from 0.24. The interval also confirms the conclusion since 0.24 it's inside of the interval calculated.

Part c

The confidence level assumed was 99%, so then the signficance is given by $\alpha=1-confidence=1-0.99=0.01$

6 0

2 years ago