A radioactive element has a half-life of 400 years. How much of 100 grams would remain after 40 years?

PEMDAS = Parentheses, Exponents, Multiplication, Division, Addition, Subtraction

First, subtract the numbers in the parentheses, then multiply by 11.

(12 - 9) = (3)

3 x 11 = 33

19 + 11 - 12^2 ÷ 3(33) - 7

Now, just multiply 33 by 3, and then square 12 (12 x 12).

19 + 11 - 144 ÷ 99 - 7

Now, you can divide 144 by 99, this is an infinite number, so..

144 ÷ 99 = 1.455

19 + 11 - 1.455 - 7

Finally add, then subtract.

30 - 1.455 - 7

28.545 - 7

The final answer is 21.545.

Answer:

Did you mess up the question? This doesn't make any sense. If you post a new question I can help! Otherwise uhhh x=9*2 ???

Answer:

The probability that the mean of a sample of 36 cars would be less than 3245 miles

P(X⁻≤3245) = 0.975

Step-by-step explanation:

Step(i):-

The mean number of miles between services

                   μ= 3408 miles  

The Variance of miles between services

                σ² = 249,001

                σ = √249,001 = 499

Let 'X' be a random variable in a normal distribution

Given sample size 'n' =36

Step(ii):-

           [tex]Z = \frac{x^{-}-mean }{\frac{S.D}{\sqrt{n} } }[/tex]

          Z = -163/83.16 = 1.96

The probability that the mean of a sample of 36 cars would be less than 3245 miles

P(X⁻≤3245)  =   P(Z≤1.96)

                   =   0.5 + A(1.96)

                   =  0.5 + 0.4750

                  =   0.975

Final answer:-

The probability that the mean of a sample of 36 cars would be less than 3245 miles

P(X⁻≤3245) =0.975

Answer:

It's C

Step-by-step explanation:

Multiply the length by the width and you are going to do that by multiplying 4x by 2x and 4 and also multiply -6 by 2x and 4. and then you simplify and you should get the equation C

Answer:

Step-by-step explanation:

Vertex

Answer:

B

Step-by-step explanation:

Answer:

36miles

Step-by-step explanation:

Given parameters:

Rate  = 12mph

Time  = 3hr

Unknown:

Distance = ?

Solution:

The given rate amount is the speed. Speed is the distance divided by the time.

It is mathematically expressed as:

         Speed  = [tex]\frac{distance}{time}[/tex]  

    Distance  = Speed x time

    Distance  = 12 x 3  = 36miles

Answer:p

pn gv=0753vc

Step-by-step explanation:

Answer:

+80=0 at the end of the thing

Step-by-step explanation:

Answer:

81

Step-by-step explanation:

-9+9= 18

9x9= 81

they have to use the same number, but one is added and the other is multiplied

Answer:

A

Step-by-step explanation:

2^-2 is -4 I believe and then multiplied by three would be -12

Answer:

13/-3

Step-by-step explanation:

Answer:

-13/3

Step-by-step explanation:

The slope is rise over run.

From the first point to the other, the line goes 13 units up and -3 units to the right.

Putting it in the form of rise over run we have:

13/-3 which is the same as -13/3

I'm pretty sure it is the fourth answer.

Answer:

It should be -7

Step-by-step explanation:

since it starts from D to B in the number line

Answer:

6:5

Step-by-step explanation:

i think this is it as I square rooted it and go that

Answer:

the first one; 3*1/10^-4

Step-by-step explanation:

10^-4 can be ocnverted into a fraction: 1/10^4

Answer:

3 times 1/10,000

Step-by-step explanation:

Answer:

She wins 40 games

Step-by-step explanation:

I'm not the best at explaining but 5x12=60 so then we multiply 8 by 5 aswell and bam we have 40.

Answer: c

Step-by-step explanation:

Answer:

1

Step-by-step explanation:

The equation [tex]\frac{y_{2} - y_{1} }{x_{2} - x_{1}}[/tex], the points are (-5, -3) and (2, 4), so to know which is which just do it by order, so in this case [tex]y_{1} = 4, y_{2} = -3, x_{1} = -5, x_{2} = 2[/tex] basically like i said, just in order.

So let's separate the equations into 2 for now:

[tex]y_{2} - y_{1}[/tex] = 4 - (-3) = 4 + 3 = 7

[tex]x_{2} - x_{1}[/tex] = 2 - (-5) = 2 + 5 = 7

So put it together into the fraction and it's 7/7 which is 1, so the slope is 1

Answer:

it is 8

Step-by-step explanation:

1+1+1+1+1+1+1+1

2+2+2+2

4+4

8

Answer:

8

Step-by-step explanation:

Answer:

B is the answer for the question

B IS YOUR ANSWER LOL.

Answer:

This known value does not match the measured value at the 95% confidence level.

The 95% confidence interval for value is calculated as 42.92 to 43.78%,

Step-by-step explanation:

The complete question is:

Police have a hit-and-run case and need to identify the brand of red auto paint. The percentage of iron oxide, which gives paint its red color, was determined to be 43.35 ± 0.33% by one method of analysis using five measurements. The color reference provide by the automotive manufacture is 44.21%. What can you conclude about whether the sample matches the reference at a 95% confidence level?

Student's t test is used to compare the two values .

Here n=5

Degrees of freedom =ν= n-1= 5-1=4

The value from t- table for 4 d.f at 95 % confidence interval is 2.776

The test statistic is

x`± t ∝/2(v). S/√n

43.35 ± (2.776)(0.33)/√5

= 43.35 ± 0.43

= 43.78, 42.92

Here the 95% confidence interval for μ calculated is 42.92 to 43.78%, where as color reference provided by the automotive manufacture is 44.21%.

This known value does not match the measured value at the 95% confidence level.

Answer:

Spiced eye gonna flush my toilet now ;)

Answer:

hes right

Step-by-step explanation: