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shutvik [7]
2 years ago
5

The half-life of a radioactive substance is the time required for half of a sample to undergo radioactive decay,or for the quant

ity to fall to half its original amount.Carbon 14 has a half-line of 5730 years.Suppose given samples of carbon 14 weigh 5/8 of a pound and 7/8 of a pound.What was the total weight of the samples 11,460 years ago?
Mathematics
1 answer:
NikAS [45]2 years ago
4 0

Answer:

That's two half lives. 5/8 * 2 * 2 = 20/8 = 5/2 pounds7/8 * 2 * 2 = 28/8 = 7/2 pounds

Step-by-step explanation:

Brainliest plz?

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Answer:

z=\frac{0.333 -0.3}{\sqrt{\frac{0.3(1-0.3)}{195}}}=1.01  

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Step-by-step explanation:

Data given and notation

n=195 represent the random sample taken

X=65 represent the women who complain of nausea between the 24th and 28th week of pregnancy

\hat p=\frac{65}{195}=0.333 estimated proportion of women who complain of nausea between the 24th and 28th week of pregnancy

p_o=0.3 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)  

Concepts and formulas to use  

We need to conduct a hypothesis in order to test the claim that true proportion is higher than 0.3.:  

Null hypothesis:p\leq 0.3  

Alternative hypothesis:p > 0.3  

When we conduct a proportion test we need to use the z statisitc, 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.

Calculate the statistic  

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

z=\frac{0.333 -0.3}{\sqrt{\frac{0.3(1-0.3)}{195}}}=1.01  

Statistical decision  

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

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

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