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How many significant digits are in 705.0 ?

All trailing zeros after dec. pt are sig.
all nonzero numbers are sig.
all zeros between nonzero numbers are sig.

there are 4 significant digits

7 0

3 years ago

Read 2 more answers

tp he Pew Research Center and Smithsonian magazine recently quizzed a random sample of 1006 U.S. adults on their knowledge of sc

alukav5142 [94]

Answer:

This interval (0.175, 0.225) represents the range of values that the true proportion of U.S. adults that can answer the question of 'which gas makes up the most of the atmosphere?' correctly, can take on, with a confidence level of 95%.

Step-by-step explanation:

Confidence Interval is an interval obtaimed from sample data, for the population proportion. It is an interval of range of values where the true population proportion can be found with a certain level of confidence.

Mathematically,

Confidence Interval = (Sample proportion) ± (Margin of error)

Margin of Error is the width of the confidence interval about the mean (sample proportion).

It is given mathematically as,

Margin of Error = (Critical value) × (standard Error of the sample proportion)

Critical value is obtained from the z-tables or the t-tables depending on which information is available. For distributions where information on the population standard deviation is known or it isn't know but the sample size is large enough for the sample standard deviation can approximate the population standard deviation, the z-tables is used and for those distributions whose population standard deviation information is not known, and sample size isn't large enough, the critical value is read off the t-tables.

The critical value depends on the confidence level for both the z-tables and the t-tables critical value.

The interval obtained now represents the region of values where the true population proportion can exist within, at a certain level.of confidence.

Hope this Helps!!!

7 0

3 years ago

PLEASE HELP ME ANYONE

photoshop1234 [79]

Answer:

30+a

Step-by-step explanation:

hope it helps dont report if wrong

8 0

3 years ago

The cancellation property sin−1(sin(x)) = x is valid for x in what interval

pochemuha

Answer:

It is given that : $Sin^{-1}(Sin (x) =x$

As we have to find the Domain of $Sin^{-1}(Sin (x)$ .

-1 ≤ sin x ≤1

$Sin^{-1}(-1)\leq Sin^{-1}(Sin x)\leq Sin^{-1}(1)\\\frac{-\pi}{2}\leq x\leq \frac{\pi }{2}$

So it is defined for x lying between $(\frac{-\pi}{2}, \frac{\pi }{2})$ .

As meaning of Domain is those values of x for which any function f(x) is defined.

4 0

3 years ago

An automobile manufacturer claims that its van has a 31.3 miles/gallon (MPG) rating. An independent testing firm has been contra

Yuliya22 [10]

Answer:

$z=\frac{\bar X-\mu_o}{\frac{\sigma}{\sqrt{n}}}$ (1)

$z=\frac{31.1-31.3}{\frac{1.3}{\sqrt{140}}}=-1.82$

$p_v =2*P(z$

If we compare the p value and the significance level given $\alpha=0.02$ we see that $p_v>\alpha$ so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, so we can conclude that the true mean is NOT significantly different from 31.3 at 2% of signficance.

Step-by-step explanation:

Data given and notation

$\bar X=31.1$ represent the sample mean

$\sigma=1.3$ represent the population standard deviation for the sample

$n=140$ sample size

$\mu_o =31.3$ represent the value that we want to test

$\alpha=0.02$ represent the significance level for the hypothesis test.

z would represent the statistic (variable of interest)

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

State the null and alternative hypotheses.

We can assume that we conduct a hypothesis in order to check if the true mean is equal to 31.3 , the system of hypothesis would be:

Null hypothesis: $\mu =31.3$

Alternative hypothesis: $\mu \neq 31.3$

Since we know the population deviation, is better apply a z test to compare the actual mean to the reference value, and the statistic is given by:

$z=\frac{\bar X-\mu_o}{\frac{\sigma}{\sqrt{n}}}$ (1)

z-test: "Is used to compare group means. Is one of the most common tests and is used to determine if the mean is (higher, less or not equal) to an specified value".

Calculate the statistic

We can replace in formula (1) the info given like this:

$z=\frac{31.1-31.3}{\frac{1.3}{\sqrt{140}}}=-1.82$

P-value

Since is a two-sided test the p value would be:

$p_v =2*P(z$

Conclusion

If we compare the p value and the significance level given $\alpha=0.02$ we see that $p_v>\alpha$ so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, so we can conclude that the true mean is NOT significantly different from 31.3 at 2% of signficance.

5 0

3 years ago