Tim Simpson writing in the Ealing & Acton Gazette today showed his lack of mathematics. He pointed out that the last five rises in council tax added up to 49.7%. His calculation was 4.7% + 4.9% + 6.8% + 25.9% + 7.4% = 49.7%. With a bit more attention in maths classes he would have known that percentages need to be multiplied, not added. The correct calculation would have been 1 * 1.047 * 1.049 * 1.068 * 1.259 * 1.074 = 1.586 or 58.6%.
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[…] If you wonder about the Gazette’s reporting you should certainly worry about their maths. They take five year’s worth of percentage rises and add them up. To have any mathematical sense they need to be multiplied. Doh! I pointed this out on 24th February when they first used the figures like this (see previous posting). […]