Apps. and Interpretation for IBDP Maths Ebook 1 | Page 391

Answers
Chapter 23
Exercise 97
Exercise 96
96.1 (a) H
0
: The number of heads
follows the assigned
distribution
(b) 10
(c) 3
(d)
(e)
� � 6.93
2
calc
The null hypothesis is not
rejected as
� � 7.815
2
calc
96.2 (a) H
0
: The last digits are evenly
distributed
(b) 10
(c) 9
(d) 15.8
(e) The null hypothesis is not
rejected as
� � 16.919
2
calc
96.3 (a) H
0
: The number of emails
received on each day follows
the assigned distribution
(b) a � 4 , b � 5
(c) 5
(d) p-value � 0.0907
(e)
The null hypothesis is not
rejected as p-value � 0.05
96.4 (a) H
0
: The outcomes follows
the assigned distribution
(b) 30
(c) 6
(d) p-value � 0.0000496
(e)
The null hypothesis is
rejected as p-value � 0.01
97.1 (a) (i) H
0
: The examination
results and the
corresponding
sections are
independent
(ii) H
1
: The examination
results and the
corresponding
sections are not
independent
(b) 2
(c)
(d)
� � 17.4
2
calc
The null hypothesis is
2
rejected as � � 5.991
calc
97.2 (a) (i) H
0
: The nationality
of children and the
choices of their most
favourite fruits are
independent
(ii) H
1
: The nationality
of children and the
choices of their most
favourite fruits are
not independent
(b) 6
(c)
(d)
p-value �4.57 � 10
�10
The null hypothesis is
rejected as p-value � 0.01
97.3 (a) H
0
: The age of adults and
their preferences are
independent
(b) x � 13, y � 39
(c) 4
(d)
(e)
p-value �4.70�
10
�7
The null hypothesis is
rejected as p-value � 0.05
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