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nikdorinn [45]
2 years ago
9

If 12g of a radioactive substance are present initially and 8yr later only 6g remain, how much if the substance will be present

after 13 years?
Mathematics
1 answer:
Brums [2.3K]2 years ago
5 0

The weight of substance remaining after 13 years is 2.25 g.

Given:

Present weight of substance = 12 g

After 8 years weight remains = 6 gm

Now, weight loss in 8 year will be,

12-6=6 gm

So, weight loss in 1 year will be,

\dfrac{6}{8} =\dfrac{3}{4}

Total weight loss in 13 year will be,

\dfrac{3}{4}\times13=9.75

The weight of substance remaining after 13 years will be,

12- 9.75 = 2.25 \;\rm g

Therefore, the weight of substance remaining after 13 years is 2.25 g.

To know more about radioactive decay, refer to the link:

brainly.com/question/12116123

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Answer:

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The sample standard deviation, s = \sqrt{\frac{\sum \left ( x-\bar{x} \right )^{2}}{n-1}}=0.1291

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b. Degree of freedom: df = n-1 = 3

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c. The Hypotheses are:

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t=\frac{\bar{x}-\mu}{s/\sqrt{n}}=8.52

The p-value is: 0.0017

We reject the null hypothesis because p-value is less than 0.05 . This indicates that the data gave good evidence to support this theory.

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