Date | May 2014 | Marks available | 2 | Reference code | 14M.2.sl.TZ2.4 |
Level | SL only | Paper | 2 | Time zone | TZ2 |
Command term | Find | Question number | 4 | Adapted from | N/A |
Question
Let A and B be independent events, where P(A)=0.3 and P(B)=0.6.
Find P(A∩B).
[2]
a.
Find P(A∪B).
[2]
b.
On the following Venn diagram, shade the region that represents A∩B′.
[1]
c(i).
Find P(A∩B′).
[2]
c(ii).
Markscheme
correct substitution (A1)
eg 0.3×0.6
P(A∩B)=0.18 A1 N2
[2 marks]
a.
correct substitution (A1)
eg P(A∪B)=0.3+0.6−0.18
P(A∪B)=0.72 A1 N2
[2 marks]
b.
A1 N1
c(i).
appropriate approach (M1)
eg 0.3−0.18, P(A)×P(B′)
P(A∩B′)=0.12 (may be seen in Venn diagram) A1 N2
[2 marks]
c(ii).
Examiners report
[N/A]
a.
[N/A]
b.
[N/A]
c(i).
[N/A]
c(ii).