Answer: The mean and standard deviation are 567.2 and 89.88 resp.
Step-by-step explanation:
Since we have given that
For 370 parts per million = 7% = 0.07
For 440 parts per million = 10% = 0.10
For 550 parts per million = 49% = 0.49
For 670 parts per million = 34% = 0.34
So, Mean of the carbon dioxide atmosphere for these trees would be
![E[x]=370\times 0.07+440\times 0.1+550\times 0.49+670\times 0.34=567.2](https://tex.z-dn.net/?f=E%5Bx%5D%3D370%5Ctimes%200.07%2B440%5Ctimes%200.1%2B550%5Ctimes%200.49%2B670%5Ctimes%200.34%3D567.2)
And
![E[x^2]=370^2\times 0.07+440^2\times 0.1+550^2\times 0.49+670^2\times 0.34=329794](https://tex.z-dn.net/?f=E%5Bx%5E2%5D%3D370%5E2%5Ctimes%200.07%2B440%5E2%5Ctimes%200.1%2B550%5E2%5Ctimes%200.49%2B670%5E2%5Ctimes%200.34%3D329794)
So, Variance would be
![Var\ x=E[x^2]-E[x]^2=329794-567.2^2=8078.16](https://tex.z-dn.net/?f=Var%5C%20x%3DE%5Bx%5E2%5D-E%5Bx%5D%5E2%3D329794-567.2%5E2%3D8078.16)
So, the standard deviation would be

Hence, the mean and standard deviation are 567.2 and 89.88 resp.
Answer: 94
Step-by-step explanation:
Let's use the "elimination by addition/subtraction" method to solve this system for x and y.
<span> -8x=72-16y
4x=-92+16y <= Mult. all 3 terms by 2: 8x = - 184 + 32y
Now combine the following, column by column:
</span><span> -8x= 72-16y
</span>8x = - 184 + 32y
-----------------------
0 = -112 + 16y. Solving for y, 16y = 112, and y = 7.
Now subst. 7 for y in either of the original equations and calculate x:
<span>4x=-92+16(7) => 4x = -92 + 112 = 20. Then x = 5.
Solution is 5, -7 (or, better written) (5, - 7).</span>
Red line shows
y=x^2-4 , cause it's going through point (0,-4)
So blue line shows
y= -x^2+1 Point (1,0) belong to it , moreover x factor is negative , so the arms of parabola will go down
Have nice evenig :)
Greetings From Poland.