a) A hospital has developed a test to discover if new born babies have a certain type of mental…

a) A hospital has developed a test to discover if new born babies have a certain type of mental disorder. From past records it is known that the probability that a baby has this disorder is 0.003.If the baby does have the disorder, the test will be positive 98% of the time. If the baby does not have the disorder, the test will be negative 99% of the time. The test is administered on a newborn baby and is positive. What is the probability that the

baby has the disorder? [4 Marks ]

b) “Statistical enquiries mean some sort of investigation by any agency whatsoever wherein relevant information is collected in numbers rather than words”. Briefly explain the stages

involved in any statistical enquiry. [12 Marks]

c) Giving relevant examples distinguish between descriptive statistics and inferential statistics. [4 Marks ] QUESTION FIVE (20 MARKS)

a) The table below shows the prices of average person’s diet and the basket of goods in the year 2000 and 2005.

Item	Price 2000	Price 2005	Quantity 2000	Quantity 2005
Steak	£2.20	£3.00	50	40
Pepper	£2.00	£2.00	2	3
Bread	£.50	£.60	80	100

Determine the Laspeyre’s price index, paashce’s price index and Fisher’s ideal index

[10 Marks]

b) In a study of the daily production of a company over 50 days, the following data was obtained.

65 76 36 48 84 55 79 51 49 48

43 21 78 35 40 45 68 33 37 61

88 45 50 53 56 67 57 42 60 34

59 62 62 65 74 61 70 73 76 55

35 41 60 74 63 58 32 26 52 82

i) Starting with a class 20-29 , group this data into a frequency distribution and plot

its frequency polygon.[4 Marks ]ii) Using assumed mean method (A=60.5), calculate the mean and standard deviation.