Page 26 - Statistics presented by Dr. Sara Ismail Aborass

9/8/2023

Example

Construct the regression line of the following data,
calculate r, a and b. Then find the unknown conc.
(in ppm) of a sample giving response 15.2 (using
equation and by interpolation)

Riboflavin (ppm) Response

0.05 2.2
0.100 5.80
0.200 12.20
0.400 22.30
0.800 43.30

49

50 Calibration graph

40

response30

20 y = 54.011x + 0.4167
10 r = 0.9982

0 1
0 0.5 X=0.274 ppm

Conc ppm

15.2=0.4167 +54.011 (x)

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