"How many pigs do you keep on the farm?" I asked professor Sweinfeaver. "You'll need brains to answer that," he replied. "All I can remember is that the number of pigs is divisible by three, it's a five-digit number and the digits are represented by the letters SWINE where BRAINS plus BRAINS equals ANSWER.

So how many pigs did the professor keep on his farm? The first correct answer opened on 12 March will win a copy of the new Chambers 21st Century Dictionary. Answers to: Perplexity, The Independent, 1 Canada Square, Canary Wharf, London E14 5DL.

15 February answers:

Nectarines (inn creates), Tangerines (green satin), Grapefruits (furriest gap)

Winner: Mrs M Boyle (Consett)