Focal length and angle of view

For this exercise, I took some pictures in our living room of the television set whilst sitting by the dining table. I used the 18 to 70 mm "kit" lens.

The zoom was at roughly 60 mm when the television appeared in the viewfinder to be at "actual" size. When printed on A4 paper, I needed to hold this at full arms length (~75cms) for the image of the television set to appear to be at "actual" size.
At the widest angle setting of 18mm, I needed to hold the A4 paper at about 25cm from my face for the image of the television to appear to be actual size.
At the highest zoom setting of 70 mm, the A4 print needed to he held at 90 cms (just beyond arms length) for the image of the television to appear to be at actual size.

A rough calculation of angle of view using the height of television screen, distance from lens to tv and size of image printed on A4 paper was 78 degrees at wide angle and about 13 degrees at 70 mm on zoom. (Taking account of the rough calculation, this tallies reasonably well with the published figures for 18 to 70 mm lens of 76 degrees to 22 degrees for a 2/3rd sensor).