AS biology question!!! urgent

[Recobaq8]

how do we calculate the "uncertainty"?

[hesho21]

its half the smallest division divided by the reading u took . for example u took a reading of 4cm from a ruler. the smallest division on the ruler is 1mm. so to calculate uncertainty , u divide the 0.05cm which is the smallest division by the reading u took which is 4cm. the percentage uncertainty would be multiply that by 100.

Hope it helped

[M-H]

By the way edexcel or cie bio?
ok for calculation uncertainty anywer
for eg. u hav a set of values- 0.6, 0.7, .0.8, 0.9
1st ul find the average value... .6+.7+.8+.9=3/4 =.75
ok then u find the diference b/w this avg value and the smallest value in ur set ie: .75-.6=.15    ->1)
u find the dfrnce b/w ur avg value but this time with the greatest value in the set..ie: .75-.9=.15 ->2)

here the dfrnce in both the cases is the same ...so ur ans is .75+/-.15
but if u had 1) bigger than 2) or 2) biger than 1)..then u wud choose the biger value...if 2) had been .17..since its greater than .15 id take that n my uncertainty wud b +/- .17.....ok??