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Irina-Kira [14]

3 years ago

11

Imagine that the price per gallon of gas with a $7 car wash is $3.32 and the price without a car wash is $3.52 When is it worth

it to buy the car wash? When is it worth it if the car wash cost $4

1 answer:

Novosadov [1.4K]3 years ago

3 0

Answer: b and d

Step-by-step explanation:it IS

You might be interested in

Which variable expression matches the word phrase? Column A Column B

erik [133]

<span>1. the sum of 12 and the quotient of 9 and a number

The responder's answer is not given but it can be 12 + (9 / n)

2. </span>the difference of 12 and the product of 9 and a number

The responder's answer would be <span>c. 12 – 9y

3</span>. the difference of 12 and the quotient of 9 and a number

The responder's answer would be <span>b. 12 – (9 ÷ y)
</span>
<span>4. 12 more than quotient of a 9 and number
</span>
The responder's answer would be<span> a. 12 + (9 ÷ y)</span>

4 0

3 years ago

Life rating in Greece. Greece has faced a severe economic crisis since the end of 2009. A Gallup poll surveyed 1,000 randomly sa

elena-s [515]

Answer:

a

The population parameter of interest is the true proportion of Greek who are suffering

While the point estimate of this parameter is proportion of those that would rate their lives poorly enough to be considered "suffering". which is 25%

b

The condition is met

c

The 95% confidence interval is $0.223 < p < 0.277$

d

If the confidence level is increased which will in turn reduce the level of significance but increase the critical value( $Z_{\frac{\alpha }{2} }$ ) and this will increase the margin of error( deduced from the formula for margin of error i.e $E \ \alpha \ Z_{\frac{\alpha }{2} }$ ) which will make the confidence interval wider

e

Looking at the formula for margin of error if the we see that if the sample size is increased the margin of error will reduce making the confidence level narrower

Step-by-step explanation:

From the question we are told that

The sample size is n = 1000

The population proportion is $\r p = 0.25$

Considering question a

The population parameter of interest is the true proportion of Greek who are suffering

While the point estimate of this parameter is proportion of those that would rate their lives poorly enough to be considered "suffering". which is 25%

Considering question b

The condition for constructing a confidence interval is

$n * \r p > 5\ and \ n(1 - \r p ) >5$

So

$1000 * 0.25 > 5 \ and \ 1000 * (1-0.25 ) > 5$

$250 > 5 \ and \ 750> 5$

Hence the condition is met

Considering question c

Given that the confidence level is 95% then the level of significance is mathematically evaluated as

$\alpha = 100 - 95$

$\alpha = 5 \%$

$\alpha = 0.05$

Next we obtain the critical value of $\frac{\alpha }{2}$ from the normal distribution table, the value is

$Z_{\frac{\alpha }{2} } = 1.96$

Generally the margin of error is mathematically represented as

$E = Z_\frac{ \alpha }{2} * \sqrt{ \frac{\r p (1 - \r p ) }{n} }$

substituting values

$E = 1.96 * \sqrt{ \frac{ 0.25 (1 - 0.25 ) }{ 1000} }$

$E = 0.027$

The 95% confidence interval is mathematically represented as

$\r p - E < p < \r p + E$

substituting values

$0.25 - 0.027 < p < 0.25 + 0.027$

substituting values

$0.223 < p < 0.277$

considering d

If the confidence level is increased which will in turn reduce the level of significance but increase the critical value( $Z_{\frac{\alpha }{2} }$ ) and this will increase the margin of error( deduced from the formula for margin of error i.e $E \ \alpha \ Z_{\frac{\alpha }{2} }$ ) which will make the confidence interval wider

considering e

Looking at the formula for margin of error if the we see that if the sample size is increased the margin of error will reduce making the confidence level narrower

5 0

3 years ago

Help out.........................................................................

solniwko [45]

3.4 = -13.6 - 3.4c + 1.7c
3.4 = -13.6 - 1.7c
1.7c = -13.6 - 3.4
1.7c = 17
c = 10

8 0

3 years ago

Read 2 more answers

Evaluate 3{-1+3[7-2(-10+8)]}

marshall27 [118]

3{-1 + 3 [ 7 - 2(-10 + 8)]} Work out ' inside' parentheses first:-

= 3{-1 + 3 [7 - 2*-2]}

= 3 { -1 + 3 [7 + 4]}

= 3 { -1 + 3*11}

= 3 * 32

= 96 answer

4 0

3 years ago

The triangular pyramid has identical equilateral triangles as its faces. Find the surface area of the pyramid.

xeze [42]

Answer: B: 140.4

Step-by-step explanation:

8 0

3 years ago