You need to find the slope
251-248. 3
------------- = --------
2005-1965. 40
Reduce the expression, if possible, by cancelling the common factors.
Exact form:
15/7
Decimal form:
2.142857 repeating
Mixed number form:
2 1/7
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)
The graph is misleading because the year’s interval is not constant.
The first year to the second year, the gap is 1 year; in the second to the
third year, the gap is 2; in the third to the fourth year is 4; and the fourth
to the fifth year is 6.
Answer:
$10 + $10 + $1 + 25¢ + 5¢
or
$20 + $1 + 25¢ + 5¢
Step-by-step explanation:
Each one must pay $21.30