User interface language: English | Español

Date November 2016 Marks available 2 Reference code 16N.1.AHL.TZ0.H_2
Level Additional Higher Level Paper Paper 1 Time zone Time zone 0
Command term Complete Question number H_2 Adapted from N/A

Question

The faces of a fair six-sided die are numbered 1, 2, 2, 4, 4, 6. Let XX be the discrete random variable that models the score obtained when this die is rolled.

Complete the probability distribution table for XX.

N16/5/MATHL/HP1/ENG/TZ0/02.a

[2]
a.

Find the expected value of XX.

[2]
b.

Markscheme

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

N16/5/MATHL/HP1/ENG/TZ0/02.a/M     A1A1

 

Note:     Award A1 for each correct row.

 

[2 marks]

a.

E(X)=1×16+2×13+4×13+6×16E(X)=1×16+2×13+4×13+6×16    (M1)

=196 (=316)=196 (=316)    A1

 

Note:     If the probabilities in (a) are not values between 0 and 1 or lead to E(X)>6E(X)>6 award M1A0 to correct method using the incorrect probabilities; otherwise allow FT marks.

 

[2 marks]

b.

Examiners report

[N/A]
a.
[N/A]
b.

Syllabus sections

Topic 4—Statistics and probability » SL 4.7—Discrete random variables
Show 78 related questions
Topic 4—Statistics and probability

View options