CAMPBELL Newman could be heading back to school following an embarrassing promotional bungle that has left him red faced.

The Premier's Ashgrove electorate office sent out a "handy conversion guide" to newly registered voters - offering to convert imperial measures to metric - but the item is riddled with errors.

The near-enough-is-good-enough conversion table has been shared on Facebook.

In online posts, bloggers say they have written to Mr Newman's office to point out the guide incorrectly advises readers that one pound equals 500 grams. In reality, a pound equals 453.6 grams.

The guide also incorrectly states one ounce is equal to 30 grams (it's 28.3) and one third of a cup equals 80ml (it's 83).

One resident said they wrote to the Premier saying the rounding of figures was far from helpful.

"An ounce is more like 28 grams and a pound is not an even 500 grams, however close it might seem - the maths on the magnet itself doesn't add up," the post read.

"One pound is listed as 500 grams and 16 ounces, and yet one ounce is listed as 30 grams. Multiplying 16 by 30 results in 480."

Another said: "This concerns me, because I would like to think anything produced by the government or one of its representatives will be meticulous in its presentation and content".

"I of course realise humans make errors all the time - but the government should highly represent and embody the ideals and qualities of the society it governs. This to me sends a message that even basic maths or the education which underlies it has little priority."

A spokeswoman from the Premier's electorate office said they had given out "many" of the guides at an Enoggera Barracks event on the weekend.

"To be honest, I've never looked at them and checked them out, I just assumed they were right," she said.

"This is honestly the first we've heard about it (the Facebook post). Yesterday was the first )complaint) we've had."

The office is currently looking into how many magnets have been circulated into the community and where the errors originated.

CORRECTION: An earlier version of this story pulled up the premier's guide for stating one metric tablespoon equalled 20ml, when our research found it was 15ml. Several readers subsequently pointed out that one metric tablespoon is equal to 15ml in the US and UK, but 20ml in Australia and New Zealand. Quest Newspapers apologises for the error and thanks those sharp-eyed readers who share our desire for accuracy.