I like percentages. A percentage means per hundred. If you have 10 beads (it could be anything as the question is about working the maths not about beads) and one is blue, what is the percentage of blue beads? You may be able to see at once that the answer is 10% but how did you do it, and if you can answer that question then you can work out the hardest of percentages. 1 in 10 beads are blue. 1/10 of the total amount is blue. Multiply numerator and denominator by 10 and you have 10/100 which is the same thing as saying 10%.

Let's do the same thing with a harder sum. What is 6.4% of 276 549? To find 1% you divide by 100, so 1% is easy, it is 2 765.549 Don't be concerned by the big numbers. They haven't changed. the only thing that has changed is the position of the decimal point. To find 6.4% you multiply 1% by 6.4. I am not going to do this for you as it isn't important. what is important is that you know how to work out percentages. Anyone can make errors with calculators but if you know what you are doing then you can check it again and make sure that you are right.

That sums it up.

## Tuesday, 14 April 2009

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