Test Scores

5
6
7
8
9

Frequency 4 2 3 5 6

( iii ) Write down the mode.

( 1 )

( iv ) Find the median score.

( 2 )

( v ) Work out the mean.

( 3 )

( b ) A student is chosen at random.

What is the probability that this student :-


( i ) scored 5 marks,

( 1 )

( ii ) scored less than 8 marks.

1 answer

(i) P(scored 5 marks) = Frequency of students with score 5 / Total number of students
= 4 / (4+2+3+5+6)
= 4 / 20
= 1/5
= 0.2

(ii) P(scored less than 8 marks) = Frequency of students with scores less than 8 / Total number of students
= (4+2+3+5) / 20
= 14 / 20
= 0.7