Ask Me Help Desk

Ask Me Help Desk (https://www.askmehelpdesk.com/forum.php)
-   Math & Sciences (https://www.askmehelpdesk.com/forumdisplay.php?f=402)
-   -   Survey probability (https://www.askmehelpdesk.com/showthread.php?t=673022)

  • Jun 20, 2012, 02:45 AM
    Kszq
    Survey probability
    A survey was done among people aged 65 years or older.It was
    found that they had a 30% of suffering from stroke.If they suffered
    from stroke,then their chances of developing cardiovascular
    complications were 70%.However,if they did not suffer fromj stroke
    then they had a 25% chance of developing cardiovascular complications.
    Find the probability of:
    I)Experiencing one of the stated health problems.
    ii)Experiencing at least one of the stated health problems.
    b)A tire manufacturer designed a new ambulance tread pattern for its
    all-weather tires.Repeated tests were conducted on ambulances of
    approximately the same weight travelling at 60 kilometres per hour.The
    tests showed that the new tread pattern enables the ambulances to stop
    completely in an average distance of 125 metres with a standard
    deviation of 6.5 meters and that the stopping distances are
    approximately normally distributed.
    I)What is the 70th percentile of the distribution of stopping distances?
    ii)What is the probability that at least 2 ambulances out of 5
    randomly selected cars in the study will stop in a distance that is
    greater than the distance calculated in part(I) above?
    iii)What is the probability that a randomly selected sample of 5
    ambulances in the study will have a mean stopping distance of at least
    130 feet?
  • Jun 20, 2012, 02:46 AM
    Kszq
    Probability
    A survey was done among people aged 65 years or older.It was
    found that they had a 30% of suffering from stroke.If they suffered
    from stroke,then their chances of developing cardiovascular
    complications were 70%.However,if they did not suffer fromj stroke
    then they had a 25% chance of developing cardiovascular complications.
    Find the probability of:
    I)Experiencing one of the stated health problems.
    ii)Experiencing at least one of the stated health problems.
    b)A tire manufacturer designed a new ambulance tread pattern for its
    all-weather tires.Repeated tests were conducted on ambulances of
    approximately the same weight travelling at 60 kilometres per hour.The
    tests showed that the new tread pattern enables the ambulances to stop
    completely in an average distance of 125 metres with a standard
    deviation of 6.5 meters and that the stopping distances are
    approximately normally distributed.
    I)What is the 70th percentile of the distribution of stopping distances?
    ii)What is the probability that at least 2 ambulances out of 5
    randomly selected cars in the study will stop in a distance that is
    greater than the distance calculated in part(I) above?
    iii)What is the probability that a randomly selected sample of 5
    ambulances in the study will have a mean stopping distance of at least
    130 feet?
  • Jun 20, 2012, 02:48 AM
    Kszq
    Maths
    Two drugs A and B were administered to two types of patients,and
    Increase in sleeping times,in hours ,noted.There were 10 patients in
    Each group,and the results were:
    A:2.1 3.1 -0.1 -0.1 2.1 3.5 -2.4 5.5 4.8 -0.16
    B:-1.1 2.1 -0.1 -1.1 3.1 0.8 -1.2 -0.6 2.5 -1.8
    Test the hypothesis that A and B are equally effective at 5% level of
    Significance.
    Q12.The following numbers give the weights of 30 students in a Biology class.
    I)Plot the frequency curve of the data.
    ii)Calculate the mean weight
    iii)Indicate the medianweight
  • Jun 20, 2012, 02:49 AM
    Kszq
    Maths
    Two drugs A and B were administered to two types of patients,and
    Increase in sleeping times,in hours ,noted.There were 10 patients in
    Each group,and the results were:
    A:2.1 3.1 -0.1 -0.1 2.1 3.5 -2.4 5.5 4.8 -0.16
    B:-1.1 2.1 -0.1 -1.1 3.1 0.8 -1.2 -0.6 2.5 -1.8

    Test the hypothesis that A and B are equally effective at 5% level of
    Significance.
  • Jun 20, 2012, 02:50 AM
    Kszq
    Mathematics help
    The following numbers give the weights of 30 students in a Biology class.
    I)Plot the frequency curve of the data.
    ii)Calculate the mean weight
    iii)Indicate the medianweight

    42 74 40 60 82 41

    53 110 76 84 50 65

    68 69 104 80 79 54

    66 49 77 90 84 42

    72 50 79 52 103 51
  • Jun 20, 2012, 02:51 AM
    Kszq
    Probability
    .The mean length of ears in a population of ears of a certain
    variety of wheat is 9.978cm, and the standard deviation is 1.441
    cm.What is the probability of occurrnce of;
    a) An ear having length of 12cm or more.
    b)An ear of 6.536 or less
  • Jun 20, 2012, 02:52 AM
    Kszq
    Mean
    An incomplete distribution is given below:

    Classes 10-20 20-30 30-40 40-50 50-60 60-70 70-80 TOTAL

    Frequency 12 30 a 65 b 25 18 229

    You are further given that the median is 46.Use the median formula to
    Fill in the missing frequencies,and calculate the mean.
  • Jun 20, 2012, 02:53 AM
    Curlyben
    Please refer to this announcement

    Quote:

    Do not simply retype or paste a question from your book or study material

    We won't do your homework questions for you.
    You were given the assignment for you to learn.

    If you come up with your own answer and post it for us to critique that is within reason.

    If you have some SPECIFIC questions that you couldn't find or didn't understand, we may help with that.
    But this is your assignment, so show us you have at least attempted to complete it on your own.
  • Jun 20, 2012, 02:53 AM
    Kszq
    Statistics
    )For a group of 200 students,the mean and standard devaiations
    were found to be 40 and 15 respectively.Later on,it was discovered
    that the scores 43 and 35 were misread as 34 and 53 respectively.Find
    the corrected mean and standard deviation corresponding to the
    corrected figures.
    b)Find the variance of the following set of observations,using an
    assumed mean of 55.

    Class(X) Frequency(f)
    20-30 3
    30-40 61
    40-50 132
    50-60 153
    60-70 140
    70-80 51
    80-90 2
  • Jun 20, 2012, 02:54 AM
    Kszq
    Probability
    a)The height(cm) and weight(Kg) of a sample of eight adult persons
    are as shown below:

    Height 177 163 168 174 184 184 171 173

    Weight 71 67 62 73 80 85 69 77

    I)Find a regression line to the data.
    ii)Find the pearson correlation coefficient between height and
    weight.What conclusion can you make?
    b)The probability that a patient recovers from a certain disease is
    0.3.If 5 people are known to have contracted this disease,what is the
    probability that,
    I)At least 3 survive.
    ii)From 2 to 4 survive.
    iii)Exactly 4 survive.

  • All times are GMT -7. The time now is 06:32 PM.