Skip to content

Course home

Sign up

2 Unit AS 2: Applied Mathematics

EasyMediumHard
123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282
Question 148

An environmental study measures the nitrogen concentration, xxx mg/L, and the dissolved oxygen level, yyy mg/L, at 15 different sites along an industrial canal. The data are summarised as follows:

Sxx=2 400S_{xx} = 2\,400Sxx​=2400 ∑y=1 020\sum y = 1\,020∑y=1020 ∑y2=72 400\sum y^2 = 72\,400∑y2=72400 Sxy=−1 950S_{xy} = -1\,950Sxy​=−1950

a.

Determine the value of SyyS_{yy}Syy​.

[2]
b.

Calculate the product moment correlation coefficient for these data, giving your answer to 3 significant figures.

[2]
c.

Interpret the value of the correlation coefficient in the context of the study.

[1]
d.

A scientist converts the nitrogen concentration into grams per litre, www, such that w=x1000w = \frac{x}{1000}w=1000x​.

State the value of SwwS_{ww}Sww​.

[1]
e.

State the value of the product moment correlation coefficient between www and yyy.

[1]
Markscheme

2 Unit AS 2: Applied Mathematics Questions

  1. A Level
  2. /Maths
  3. /2 Unit AS 2: Applied Mathematics

Question bank