How does a mans brain work?

Yesterday one of my fellow co. workers ("idiots?") was expecting a customer to come down and look at some carpet tile samples but he had to go out so he gave them to me to show. "how much a square metre are they?" says I knowing the customer would ask this question. "oh about ten pound + the V.A.T" says my fellow co. worker "what all of them?" "yes." Well I thought that doesn't sound right to me so I asked for the exact costs. One range was £10 per m2 another £12 per m2 and the third was £19 per m2 all plus the V.A.T. so if the customer had liked the third range and I had told hime they were £10 per m2 I would have been way off beam with the cost through no fault of my own. I wonder if my fellow co. worker would have admitted it was his mistake I don't think so!