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-BARSIC- [3]
3 years ago
12

A sample of a material has 40000 radioactive particles in it today. Your grandmother measured 80000 radioactive particles in it

80 years ago. How many radioactive particles will the sample have 80 years from today?
Mathematics
1 answer:
vichka [17]3 years ago
7 0

Answer:

20,000 particles

Step-by-step explanation:

Here we are given that the amount if radioactive particles has come down to 40,000 from 80,000 in 80 years . Hence by the definition of Half Life,the half life of the item is 80 years.

Now we are asked to guess the number of radioactive particles after 80 years. As we already know that , the half life of material is 80 years , the number of radioactive particles will be reduced to its half in 80 years. Hence the number of radioactive particles after 80 years is 20,000

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Given a real number x and a positive integer k, determine the number of multiplications used to find x2k starting with x and suc
Alex

Answer: It is a more efficient way to find x2k than by multiplying x by itself the appropriate number of times.

Step-by-step explanation: Please find the attached file for the solution

8 0
3 years ago
The market and Stock J have the following probability distributions:
denis-greek [22]

Answer:

1) E(M) = 14*0.3 + 10*0.4 + 19*0.3 = 13.9 \%

2) E(J)= 22*0.3 + 4*0.4 + 12*0.3 = 11.8 \%

3) E(M^2) = 14^2*0.3 + 10^2*0.4 + 19^2*0.3 = 207.1

And the variance would be given by:

Var (M)= E(M^2) -[E(M)]^2 = 207.1 -(13.9^2)= 13.89

And the deviation would be:

Sd(M) = \sqrt{13.89}= 3.73

4) E(J^2) = 22^2*0.3 + 4^2*0.4 + 12^2*0.3 =194.8

And the variance would be given by:

Var (J)= E(J^2) -[E(J)]^2 = 194.8 -(11.8^2)= 55.56

And the deviation would be:

Sd(M) = \sqrt{55.56}= 7.45

Step-by-step explanation:

For this case we have the following distributions given:

Probability  M   J

0.3           14%  22%

0.4           10%    4%

0.3           19%    12%

Part 1

The expected value is given by this formula:

E(X)=\sum_{i=1}^n X_i P(X_i)

And replacing we got:

E(M) = 14*0.3 + 10*0.4 + 19*0.3 = 13.9 \%

Part 2

E(J)= 22*0.3 + 4*0.4 + 12*0.3 = 11.8 \%

Part 3

We can calculate the second moment first with the following formula:

E(M^2) = 14^2*0.3 + 10^2*0.4 + 19^2*0.3 = 207.1

And the variance would be given by:

Var (M)= E(M^2) -[E(M)]^2 = 207.1 -(13.9^2)= 13.89

And the deviation would be:

Sd(M) = \sqrt{13.89}= 3.73

Part 4

We can calculate the second moment first with the following formula:

E(J^2) = 22^2*0.3 + 4^2*0.4 + 12^2*0.3 =194.8

And the variance would be given by:

Var (J)= E(J^2) -[E(J)]^2 = 194.8 -(11.8^2)= 55.56

And the deviation would be:

Sd(M) = \sqrt{55.56}= 7.45

8 0
3 years ago
What is the slope for 4y-2x=8
oksian1 [2.3K]

Answer:

1/2

Step-by-step explanation:

8 0
3 years ago
Read 2 more answers
Need help fast!! Mark brainliest
Svetach [21]

Alrighty Daniel I think I've figured it out for you. A and B are 55° each, and then C is 70°. Hope I've helped!!

3 0
3 years ago
Help please.! and thank you
Alexxx [7]

Answer:

common difference is 4

Step-by-step explanation:

12-4=8

8-4=4

8 0
2 years ago
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