Apps. and Interpretation for IBDP Maths Ebook 2 | Page 290

Your Practice Set – Applications and Interpretation for IBDP Mathematics
3 . The following table shows the inner diameters of 60 plastic tubes produced in a factory :
Inner diameter ( mm ) d � 10 10 �d
� 12 12 �d
� 14 d � 14 Frequency 7 16 22 15
A
2
� goodness of fit test is conducted at a 5 % significance level to determine whether the data can be modelled by Normal distribution with parameters N ( 13 , 4 ) .
( a )
Write down the null hypothesis of the test .
[ 1 ]
( b )
( i )
Write down the value of the expected frequency of the category “ d � 10
”.
( ii ) Hence , write down the degree of freedom of the test .
( c ) Find the p -value .
( d ) State the conclusion of the test with a reason .
[ 2 ]
[ 2 ]
[ 2 ]
4 .
The following table shows the weights of 300 cats living in a castle :
Weight ( kg )
w �
3
3
�w �
3.5
3.5
�w �
4
w �
4
Frequency
49
131
83
37
A
2
� goodness of fit test is conducted at a 1 % significance level to determine whether the data can be modelled by Normal distribution with parameters N ( 3.4 , 0.15 ) .
( a ) Write down the null hypothesis of the test .
( b ) Write down the value of the expected frequency of the category “ w � 4 ”.
( c ) Write down the degree of freedom of the test .
( d ) Find the p -value .
( e ) State the conclusion of the test with a reason .
[ 1 ]
[ 1 ]
[ 1 ]
[ 2 ]
[ 2 ]
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