Let 
denote the value on the 
-th drawn ball. We want to find the expectation of 
, which by linearity of expectation is
![E[S]=E\left[\displaystyle\sum_{i=1}^5B_i\right]=\sum_{i=1}^5E[B_i]](https://tex.z-dn.net/?f=E%5BS%5D%3DE%5Cleft%5B%5Cdisplaystyle%5Csum_%7Bi%3D1%7D%5E5B_i%5Cright%5D%3D%5Csum_%7Bi%3D1%7D%5E5E%5BB_i%5D)
(which is true regardless of whether the 
are independent!)
At any point, the value on any drawn ball is uniformly distributed between the integers from 1 to 10, so that each value has a 1/10 probability of getting drawn, i.e.
and so
![E[X_i]=\displaystyle\sum_{i=1}^{10}x\,P(X_i=x)=\frac1{10}\frac{10(10+1)}2=5.5](https://tex.z-dn.net/?f=E%5BX_i%5D%3D%5Cdisplaystyle%5Csum_%7Bi%3D1%7D%5E%7B10%7Dx%5C%2CP%28X_i%3Dx%29%3D%5Cfrac1%7B10%7D%5Cfrac%7B10%2810%2B1%29%7D2%3D5.5)
Then the expected value of the total is
![E[S]=5(5.5)=\boxed{27.5}](https://tex.z-dn.net/?f=E%5BS%5D%3D5%285.5%29%3D%5Cboxed%7B27.5%7D)
Answer:
- 35
Step-by-step explanation:
2(x - 7) = 3(x+7)
2x - 14 = 3x + 21
- 21 - 14 = 3x - 2x
x = - 35
Rechecking :
2(-35 - 7) = 3 (-35 +7)
- 84 = - 84
I hope im right!!!
22. 30 degrees because line DB bisects(meaning cuts in half) angle ABC so DBC should be 30 degrees because 30+30 is 60 which is what angle ABC is.
23. 60 degrees because if we assume that it is a parallelogramand that the opposite angle are congruent.
24. 120 degrees because a quadrilatteral has sides that will equal to 360 degrees, and I said that a parallelogram will have its opposite angles congruent we take away 120 from 360 (from the previous angles ABC and BCD) we end up with 240, we divide 240 by 2 and end up with 120 degrees
25. 60 degrees. I found that angle DCB is 120 degrees so angles DCB and DCE are supplementary(add up to 180 degrees) and we subtract 120 from 180 which is 60 degrees.
26. 60 degrees vertical to angle DCE.
27. 120 degrees supplementary to DCE
- 3x + 2x + 5 + 5x + 15 = 180 [angles on a line add to 180 degrees]
- 10x + 20 = 180 [combine like terms]
- 10x = 160 [subtract 20 from both sides]
- x = 16 [divide both sides by 10]
Arc AB measures 3(16) = 48 degrees.
Arc BC measures 2(16) + 5 = 41 degrees.
Answer:
area=432
Step-by-step explanation:
use the Pythagoras theory now that you know the width and you'll get the length and the width then you multiply both of them hope it helps you.
