2 . The relationship between the body temperature and the pulse rate of the students from a sports team is investigated . Six students from the group A of the team are first medically examined and their body temperature and their pulse rates are recorded in the table below .
Student A B C D E F
|
Body Temperature ( x
C
)
|
35.8 |
36.2 |
36.4 |
36.7 |
37.4 |
37.1 |
|
Pulse Rate ( y beats per minute
)
|
80 |
81 |
87 |
117 |
100 |
93 |
( a ) The relationship between the variables is modelled by the regression equation y �ax � b .
( i ) Write down the value of a and of b .
( ii ) Hence , estimate the pulse rate of a student whose body temperature is 37 C .
( b ) ( i ) Write down the correlation coefficient .
( ii ) State which two of the following describe the correlation between the variables .
positive |
strong |
zero |
negative |
weak |
moderate |
[ 4 ]
[ 3 ]
A similar investigation has been completed last year . The pulse rates of 100 students were recorded and the data was presented as follows :
Pulse Rate ( y beats per minute ) Frequency 75 � y � 85
16
85 � y � 95 23
95 � y � 105 32
105 � y � 115 12
115 � y � 125
17
Someone claims that the distribution of the data is expected to be evenly distributed . Hence , a significance level .
2
� goodness of fit test is conducted at a 5 %
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