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## #1 Exercises » probability » 2010-09-14 05:10:29

samuel baffoe
Replies: 10

1) A man is given n keys, in random order of which only one will unlock his door. He tries them one by one (without replacement). find P(man succeeds on k*th trial)

## #2 Exercises » normal distribution » 2010-09-01 01:45:39

samuel baffoe
Replies: 1

the data show the number of games played each year by sammy. determine if the data are approximately normally distributed.
81, 148, 152, 135, 151, 152, 159, 142,34,162, 130, 162,163,143,67,112,70

## #3 Help Me ! » probability » 2010-08-31 22:56:26

samuel baffoe
Replies: 2

let N be a positive integer and let f(x)=c2^x, x =1,2,....n
=0 elsewhere
find the value of c such that f(x) is a probability function

## #4 Help Me ! » stem and leaf, box plot » 2010-08-25 02:38:53

samuel baffoe
Replies: 2

the ff. stem and leaf plot shows the lifetime in hours of 15 long life light bulbs and 15 ever bright light bulbs

long life                ever bright

71
72             5
6 3 1 0       73             1
9 9 8 7 6 2   74             6
9 7 3 0       75       2
76             0 2 2 5 7
77             1 1 3 4 6 8
1               78
79

1. represent this information on a box plot
2. give a good reason why someone might prefer a long life light bulb give supporting details
3. give a good reason why someone might prefer an ever bright light bulb give supporting details

## #5 Help Me ! » stem and leaf, box plot » 2010-08-25 02:12:03

samuel baffoe
Replies: 1

6 3 1 0
9 9 8 7 6 2
9 7 3 0

1    71
72
73
74
75
76
77
78
79
5
1
6
2
0 2 2 5 7
1 1 3 4 6 8
Represent this information on box plot