18N.2.SL.TZ0.S_1

pestleMathematicsAASLPaper 218N· sl-4-5-probability-concepts-expected-numberssource ↗

In a group of 35 students, some take art class (A) and some take music class (M). 5 of these students do not take either class. This information is shown in the following Venn diagram.

One student from the group is chosen at random. Find the probability that

Write down the number of students in the group who take art class.

[2]

the student does not take art class.

[2]

b.i.

the student takes either art class or music class, but not both.

[2]

b.ii.

Markscheme / solution

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

valid approach (M1)

$\left( {A \cap M'} \right) + \left( {A \cap M} \right)$ , $\frac{{17}}{{35}}$ , 11 + 6

number of students taking art class = 17 A1 N2

[2 marks]

valid approach (M1)

13 + 5, 35 − 17, 18, 1 − P(A)

0.514285

P(A') = $\frac{{18}}{{35}}$ (exact), 0.514 A1 N2

[2 marks]

b.i.

valid approach (M1)

11 + 13, 35 − 6 − 5, 24

0.685714

P(A or M but not both) = $\frac{{24}}{{35}}$ (exact), 0.686 A1 N2

[2 marks]

b.ii.

Examiners’ report

[N/A]

b.i.

[N/A]

b.ii.