how to find percentages

#1 $Old$ August 18th, 2007, 10:33 PM

what is 65%of 160?
and if u could give me some sample problems to look over that would be wonderful.thank you for the help.

sir nerdalot · #2 $Old$ August 18th, 2007, 11:48 PM

in order to calculate a percentage all you need to do is times the number that you want to know the percentage of by the percentage needed and then divide by 100...

so for 65% of 160 you would...

first times it by 65... = 10400
then divide by 100... = 104

thus 65% of 160 is 104... this is because a percentage is really a short hand of the number divided by 100... (for 65 this is 65/100)... and whenever there is an 'of' in a maths question it usually means times and so it's the number times the percentage(which is a fraction)

hope that helps!!

mahurshi · #3 $Old$ September 4th, 2007, 01:40 PM

Quote:

Originally Posted by Lilveracity911 $View Post$

what is 65%of 160?
and if u could give me some sample problems to look over that would be wonderful.thank you for the help.

$x$ % of $y = \frac{x}{100} * y$

so
$65$ % of $160 = \frac{65}{100} * 160 = 104$

If you have something of the form

$x$ % of $y = z$ (where $x$ % = $x$ per cent = $x$ per $100 = \frac{x}{100}$ )

It is same as

$\frac{x}{100} * y = z$

You can get $x, y,$ and $z$ by rearranging the terms

$x = z * \frac{100}{y}$

$y = z * \frac{100}{x}$

$z = x * \frac{y}{100}$

If you use the above arrangements, you should be able to solve pretty much every percentage problem you will encounter.

Hope this helps.

Mahurshi Akilla

Patrick Murray · #4 $Old$ October 26th, 2007, 12:53 AM

Hi

You can find a whole lot of sample questions and explained solutions at
Mathematics.com.au -

There is a whole FREE section on fractions that I'm sure you'll find very useful.

All the best
Patrick Murray