Need a and d for full points Percentiles Let X be a random v

(Percentiles.) Let X be a random variable. The point pk/100 (k = 1, 2, 3,..., 100) such that . P[X

Solution

(a) X=10

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(b)F(x)=1-exp(-x) for x>0

P(X<x)=0.2

--> 1-exp(-x)=0.2

--> exp(-x) = 1-0.2=0.8

So x=- ln(0.8)

		cumulative
X	P(X)	probability
0	0.00000	0.00000
1	0.00002	0.00002
2	0.00018	0.00020
3	0.00109	0.00129
4	0.00462	0.00591
5	0.01479	0.02069
6	0.03696	0.05766
7	0.07393	0.13159
8	0.12013	0.25172
9	0.16018	0.41190
10	0.17620	0.58810
11	0.16018	0.74828
12	0.12013	0.86841
13	0.07393	0.94234
14	0.03696	0.97931
15	0.01479	0.99409
16	0.00462	0.99871
17	0.00109	0.99980
18	0.00018	0.99998
19	0.00002	1.00000
20	0.00000	1.00000
	1.00000