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Percentage increase wrong



THE recent fuel price increase is not “over 300%” as reported in various media, but over 200%.


The mistake lies in divi

ding the new price of petrol ($450) by the old price ($145,20) and multiplying by 100, giving 309,9%.


The correct calculation is: first calculate the change in price ($304,80) by subtracting the old price from the new price. Then divide the change in price ($304,80) by the old price ($145,20) and multiply by 100, giving 209,9%.


Think of it this way: if the price went up from $145,20 to $290,40 (an increase of $145,20), that would be an increase of 100%.


And if the price went up from $145,20 to $434,60 (an increase of $290,40), that would be an increase of 200%. And $450 is a bit higher than $434,60 so the increase must be a bit higher than 200%, not 300%.


Wellington Svosve,

Harare

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