8. A substance has a half life of 2.347 minutes.
a. If the initial amount of the substance was 110.4 grams, how many half-lives will have passed
before the substance decays to 6.9 grams.
b. What is the total time of the decay?

Answers

Answer 1

Answer:

a.) 4 half lives have passed

b) 9.388 minutes

Step-by-step explanation:

Formula for exponential growth / decay is given as:

[tex]A=A_0b^{\frac{t}{c}}[/tex]

Where [tex]A[/tex] is the final population

[tex]A_0[/tex] is the initial population

[tex]b[/tex] is the growth factor

[tex]c[/tex] is the time taken for the growth 'b'

[tex]t[/tex] is the amount of time

Here, we are given that:

[tex]A[/tex] = 6. 9 grams

[tex]A_0[/tex] = 110.4 grams

[tex]b = \dfrac{1}{2}[/tex]

[tex]c = 2.347[/tex] min

To find:

a.) Number of half lives taken for the decay.

b.) Total time in the decay.

Solution:

a.) Number of half lives taken for the decay is nothing but equal to [tex]\frac{t}{c}[/tex].

Putting the values in the formula, we get:

[tex]6.9=110.4\times \frac{1}2^{\frac{t}{c}}\\\Rightarrow 6.9=110.4\times 0.5^{\frac{t}{c}}\\\Rightarrow 0.0625=0.5^{\frac{t}{c}}\\\Rightarrow \dfrac{t}{c} =4[/tex]

Therefore, the answer is:

4 half lives have passed.

b.) Total time of decay. We have to find the value of [tex]t[/tex] here.

From answer of part a.):

[tex]\dfrac{t}{c} =4\\\Rightarrow \dfrac{t}{2.347} =4\\\Rightarrow t =\bold{9.388\ min}[/tex]


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Step-by-step explanation:

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Answers

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Step-by-step explanation:

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How much does Jimmy earn each week, and
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Answer:

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Step-by-step explanation:

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Answers

Answer:

a. 0.2898

b. 0.0218

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d. 0.1515

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Step-by-step explanation:

Assume that SAT scores are normally distributed with mean 1518 and standard deviation 325. Round your answers to 4 decimal places

We are using the z score formula when random samples

This is given as:

z = (x-μ)/σ/√n

where x is the raw score

μ is the population mean

σ is the population standard deviation.

n is the random number of samples

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For x = 1500, n = 100

z = 1500 - 1518/325/√100

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Probability value from Z-Table:

P(x<1500) = 0.28984

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Answers

Step-by-step explanation:

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Answers

Answer:

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Answer:

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Answers

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Answers

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Question:

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My mom translated this for me and I am writing the reply with Google Translate sorry if it sucks.

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Required:
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Answers

Answer:

Z = -6.3

Step-by-step explanation:

Given that:

[tex]\mathbf{H_o :p= 0.28}[/tex]

[tex]\mathbf{H_o :p < 0.28}[/tex]

Since the alternative hypothesis is less than 0.28, then this is a left-tailed hypothesis.

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Answers

Answer:

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Answers

Answer:

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Answers

Answer:

c = 2b

Step-by-step explanation:

First, find the cost of one water bottle by dividing the total cost by the number of water bottles:

12/6

= 2

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Marine biologists have been studying the effects of acidification of the oceans on weights of male baluga whales in the Arctic Ocean. One of the studies involves a random sample of 16 baluga whales. The researchers want to create a 95% confidence interval to estimate the true mean weight of male baluga whales. Their data follow a normal distribution. The population standard deviation of weights of male baluga whales is ????=125 kg, and the researchers feel comfortable using this standard deviation for their confidence interval.
Assuming the relevant requirements are met, calculate the margin of error in estimating the true mean weight of male baluga whales in the Artic Ocean.
a. 15.31 kg
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d. 80.49 kg

Answers

Answer:

c. 61.25 kg

Step-by-step explanation:

The margin of error in estimating the true mean weight of male baluga whales in the Artic Ocean.

a. 15.31 kg

b. 51.40 kg

c. 61.25 kg

d. 80.49 kg

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95% confidence interval = 1.96

Standard deviation = 125kg

n = 16 samples

Margin of error= 1.96 × 125/√16

= 1.96 × 125/4

= 245/4

= 61.25kg

The margin of error in estimating the true mean weight of male baluga whales in the Artic Ocean is 61.25kg

89.36 in word form i have it in expanded form not word form though pls help ??????????????????????????????????????????????????????????????????????///

Answers

Answer:

eighty-nine and thirty-six hundredths

or, simpler:

eighty-nine point thirty-six

or, even simpler:

eighty-nine point three six

Answer:

eighty-nine and thirty-six hundredths

Step-by-step explanation:

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