This exercise ended up being more difficult than expected. I initially took the photos on 17/1/12 but only just finished doing the measurements today as it turned out I needed a partner to help me. I used my 18-200mm lens to complete this exercise and used the war memorial near Purley as my subject.
DSC_0016 : 50mm focal length
Distance from me to make subject appear same size as object = 200cm behind
DSC_0017 : 18mm focal length