Republic of Mathematics blog

Posts Tagged ‘decimals

Save 30%, be 30% better off?

Posted by: Gary Ernest Davis on: February 22, 2011

A travel advertisement running, currently in the US, says you can save 30% on travel costs, and so be 30% better off. Is that right? How about 50% off? To make it easier to think about, let’s think how much we would save if we got 50% off the price of something. Suppose some item […]

So you think you know how to multiply decimals?

Posted by: Gary Ernest Davis on: February 12, 2010

Finite and infinite decimals In school students are taught how to add , subtract, and multiply, – but usually not divide – decimal numbers. There is a big catch however. The decimal numbers are not infinite decimals, such as we would obtain from or The decimal numbers dealt with in school are all finite decimal […]