(a) Plant A was grown in soil with a low concentration of nitrates - Edexcel - GCSE Biology - Question 4 - 2012 - Paper 1

To find the mean leaf width for plant B, we first need to add the widths of the leaves measured:

• Widths from Plant B: 11.8 cm, 10.3 cm, 11.2 cm

Next, we sum these values:

$ext{Total width} = 11.8 + 10.3 + 11.2 = 33.3 ext{ cm}$

Now, to find the mean, we divide the total width by the number of measurements (which is 3):

ext{Mean} = rac{33.3}{3} = 11.1 ext{ cm}

Therefore, the mean leaf width for plant B is 11.1 cm.