Skip to content

Course home

Sign up

2.2.2 Scatter diagrams and correlation

EasyMediumHard
12345678910111213141516171819202122232425262728293031323334353637383940414243444546474849505152535455565758596061626364656667686970717273747576777879808182
Question 14

A biologist studying bacterial growth records the incubation time, ttt minutes, and the mass of nutrients consumed, mmm milligrams, for n=15n = 15n=15 separate samples. Each sample is initially provided with a petri dish containing 18.018.018.0 mg of nutrient. The summary statistics for these 151515 samples are as follows:

∑t=202.5,∑m=49.5,∑tm=745.2,Stt=1440.0,Smm=7.5 \sum t = 202.5, \quad \sum m = 49.5, \quad \sum tm = 745.2, \quad S_{tt} = 1440.0, \quad S_{mm} = 7.5 ∑t=202.5,∑m=49.5,∑tm=745.2,Stt​=1440.0,Smm​=7.5
a.

Calculate the product moment correlation coefficient between ttt and mmm.

[3]
b.

The mass of nutrient remaining in the dish at the end of the incubation period is recorded as RRR milligrams. (i) Write down an equation for RRR in terms of mmm. (ii) State the value of the product moment correlation coefficient between RRR and mmm.

[2]
c.

State the value of the product moment correlation coefficient between ttt and RRR.

[1]
Markscheme

2.2.2 Scatter diagrams and correlation Questions

  1. A Level
  2. /Maths
  3. /2.2.2 Scatter diagrams and correlation

157 exam-style questions on AQA A Level Maths 2.2.2 Scatter diagrams and correlation. Each one has a worked solution and a mark scheme showing where the marks go.

Question bank