Exercise 8

Q1.X: Number of patients admitted per week

X ~poisson(7) ; where= 7

The probability mass function (or) of X would be

, for

(a) X: The Number of patients admitted on a particular day

x /
0 / 0.3679
1 / 0.3679
2 / 0.1839
3 / 0.0613
….. / …..
Total / 1.0000

X ~poisson(1)

The of X would be

, for

(i) No patients admitted:

= = = 0.3679

(ii) At least 2 patients admitted:

=1[0.3679+ 0.3679] =10.7348= 0.2652

(b) (i)

Hospital is expected to admit 14 patients in 2 weeks.

(ii)

Hospital is expected to admit 28 patients in one month.

x /
0 / 0.0498
1 / 0.1494
2 / 0.2240
3 / 0.2240
4 / 0.1680
….. / …..
Total / 1.0000

Q2.X: Number of deaths per year from a cancer

X ~poisson(3) ; where=3

The of X would be

, for

(a) Not more than 2 deaths in a year

=

= 0.0498 + 0.1494 + 0.2240 = 0.4232

(b)At least 2 deaths in a year

= 1[0.0498 + 0.1494] = 10.1992 = 0.8008

(c) exactly 3 deaths in a year

= 0.2240

(d) exactly 4 deaths in 4months

X: Number of deaths in 4 months from cancer

X ~poisson(1)

The of X would be

, for

Exactly 4 Deaths

= 0.0153

Q3.X: Number of cases of breast cancer diagnosed in each year

X ~poisson(6) ; where=6

The of X would be

, for

(a) No new cases in a year

== = 0.0025

(b) Twonew cases in 6 months

X: Number of new cases of cancer in 6months

X ~poisson(3)

== 0.2240

Q8.X: Number of pus cells in the urine of healthy person per one cm3

X ~poisson(2) ; where=2

The of X would be

, for

(a) No pus cells in one cm3

== = 0.1353

(b) Twopus cells in½ cm3

X: Number of pus cells in ½ cm3 of urine

X ~poisson(1)

= = 0.3679

Q4.Let Z ~ N(0,1) ; and

(a) = 0.9131 (b) = 1−

= 1−0.9918=0.0082

(c) = 0.9649 (d)=1−

=1− 0.9965 =0.0035

(e) =-=0.9821− 0.1151 = 0.867

(f) = 0

(g) =−=0.9265 −0.0091=0.9174

Q5.Let Z~ N(0,1) ; and

(a) = 0(b) =1.645(c) = − 1.96(d) =1.96

Q6.Let Z~ N(0,1) ; and

(a) =0.0078 ; From Table:

(b) =0.1290 ; From Table:

(c) =0.9956

1−=0.9956

= 1− 0.9956 = 0.0044

= 0.0044

From Table: −2.62

(d) = 0.1553

−= 0.1553

=+ 0.1553

= 0.8413 + 0.1553 = 0.9966

= 0.9966

From Table: = 0.9966 2.709

Q7.Let Z~ N(0,1) ; and

= 0.0049

1−= 0.0049

=1−0.0049 = 0.9951

= 0.9951

From Table: = 0.9951 = 2.583