Thank you Mr T, sah. I grovel in humble apology for a snap calculation and lack of common sense at the time. The corrected answer is found in my original post.
No worries tis just a bit of fun, might have a mooch through the cuboards and add a few daft items to the prize list, must admit am having visions of you running around with the t trolley at work dropping off pics and the puzzle to your workmates