OK, I know its a bit daft, but here goes:

a) How long (on average) is a plastic bag?

b) How many plastic bags does an ‘average’ person in your country use in a year?

c) Approximately how many people from your country go shopping / use plastic bags?

d) If you stretch out all of the plastic bags used by people in your country over the period of a year (end to end), how far will you get?

For the UK, I would guess:

a) = 0.4m (possibly 0.3)

b) = 5x52 = 250 bags/person/year (probably more)

c) = 20,000,000 shoppers (probably more)

d) = 250 x 0.4 x 20,000,000 = 2,000,000,000m = 2 million km.

(Assuming my maths is about right) 2 million km worth of plastic bags will get you:

- 50 times around the worlds equator
- 2 return trips to the moon + a one-way ticket