Skip to content

Course home

Sign up

2.5 Data presentation and interpretation

EasyMediumHard
1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859606162636465666768697071
Question 12

Group A contains 20 observations with mean 10 and variance 4. Group B contains 30 observations with mean 14 and variance 9.

a.

Show that the mean of all 50 observations is 12.4.

[1]
b.

Calculate the variance of all 50 observations.

[3]
c.

Explain why the combined variance is greater than either group variance.

[1]
Markscheme

2.5 Data presentation and interpretation Questions

  1. A Level
  2. /Maths
  3. /2.5 Data presentation and interpretation

278 exam-style questions on CCEA A Level Maths 2.5 Data presentation and interpretation, covering 2.5.1 Data presentation and interpretation, 2.5.2 Data presentation and interpretation, 2.5.3 Data presentation and interpretation, 2.5.4 Data presentation and interpretation, 2.5.5 Data presentation and interpretation, 2.5.6 Data presentation and interpretation, 2.5.7 Data presentation and interpretation, 2.5.8 Data presentation and interpretation, 2.5.9 Data presentation and interpretation, and 2.5 Data presentation and interpretation. Each one has a worked solution and a mark scheme showing where the marks go.

Question bank