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Friday, July 17, 2015

PERCENTS

MATH


before we begin let's get in some relevant Hebrew vocabulary so that we are advancing our Hebraic education in every circumstance

Percent
4aCuZ אחוז

FINDING PERCENTS OF A NUMBER

To find 10% of any number, all you have to do is move the decimal point of that number over one place to the left.

What is 10% of 30?
10% of 30 = 3

So how much is 20% of 30? That's easy. It's twice as much as 10 percent, or 6.

What is 20% of 520? 
10% of 520 = 52, so 20% of 520 = 104

To find 1 percent of any number, all you have to do is move the decimal point of that number over two places to the left.

1% of 4 = 0.04
1% of 520 = 5.2

In just the same way we found 20 percent by doubling 10 percent, we can now find 2 percent by doubling 1 percent.

What is 2% of 500?
1% of 500 = 5, so 2% of 500 = 2 × 5 = 10

Now, here's the really great part. We can combine these two techniques to find any percentage test writers can invent.

Let's find 23% of 600

Well, 10% of 600 = 60
So 20% of 600 = 2 × 60 = 120
And 1% of 600 = 6, so 3% of 600 = 18

So what is 23% of 600?
20% of 600 = 120
3% of 600 =18
120 + 18 = 138

CONVERTING PERCENTS TO DECIMALS
the short way to convert from a percentage to a decimal is by removing the percentage sign and moving the decimal point 2 places to the left.


Note: A percentage is just a fraction whose denominator is always 100.


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