Not exactly a simple error in arithmetic.

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Of course, what happens in local elections does not (directly at least) change the arithmetic in the House of Commons.

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If he does not, then Germany knows that the harsh budget arithmetic in the new Stability and Growth Pact will not add up even for France - let alone the likes of Spain.

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And the figures still show 50-odd per cent of pupils at the age of 11 are not by your own light properly equipped for secondary school in reading, writing and particularly in arithmetic.

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"Simply replacing the arithmetic Carli formula with the geometric Jevons formula, as will happen in RPIJ, is not optimal, " she added.

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