waecE-LEARNING
General Mathematics Paper 2,May/June. 2014  
Questions: 1 2 3 4 5 6 7 8 9 10 11 12 13 Main
General Comments
Weakness/Remedies
Strength













Question 11

Scores

1

2

3

4

5

6

Frequency

2

5

13

11

9

10

 

The table shows the distribution of outcomes when a die is thrown 50 times.  Calculate the:
(a)        mean deviation of the distribution;
(b)        probability that a score selected at random is at least a 4.

_____________________________________________________________________________________________________
Observation

This question was reported to be very popular among the candidates and their performance was commended.  They showed mastery of this aspect of the syllabus.  Majority of the candidates were reported to have obtained the following table.


1

2

2

3

6

2

5

10

2

10

3

13

39

1

13

4

11

44

0

0

5

9

45

1

9

6

10

60

2

20

 

∑f=50

∑fx=200

 

∑f |x-|=58

Using the table, mean  =   =   4. Mean deviation =    =      =   1.16.   Number of times of obtaining a score of at least a4 = 11 + 9 + 10 = 30.  Therefore probability of at least a4 =  =  or 0.6.

 

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