Dear Colibrita,

The phrase �Per cent�, (or �Percent�), refers to a specified amount in, or for, every �Hundred�.

The word �Percentage� means a rate, a number, or an amount, �Per hundred�, (for every Hundred).

So, �I will give you 5 per cent, (5%), of my bank account� means, �For every 100 units in my bank account, I will give you 5 units.  I have 300 units in my account, so I will give you 3 x 5 = 15 units, because 15 units = 5% of 300.�

300  x 5 = 15

    100

(300 divided by 100, multiplied by 5, equals 15.  Answer 15.)

To calculate a percentage increase from 7.5 (seven point five) per cent to 9.6 (nine point six) per cent is the same as a calculating the numerical increase from 7.5 to 9.6, (from seven point five to nine point six).

�9.6 � 7.5 = 2.1�.

The increase from 7.5 per cent to 9.6 per cent is 2.1 per cent.  Answer 2.1%. (Two point one per cent).

The formula for calculating a percentage, using an electronic calculator which does not have a �percent key� is as follows, (also shown above).

1)     Punch in the number which represents the figure requiring the percentage.  (For example, the amount in the bank).

2)     Divide by 100.

3)     Multiply by the percentage number.

4)     = Answer.

So, (for example), �The student population of my college is 6000 students.  25% of the students are male.  How many male students are there?�

6000 x 25  = 1500 male students.

100

(6000 divided by 100, multiplied by 25, equals 1500.  Answer 1500 male students.)

By subtracting 1500 (male students) from 6000 (total students), I know that there are 4500 female students.

If we say that XXXXX is the number for which you wish to calculate the increase, (an increase of 2.1%), the complete formula for your calculation is:

9.6 � 7.5 (XXXXX)  = ANSWER

In plain English: 1) Subtract 7.5 from 9.6.  Your percentage increase is 2.1%.

2) Divide by 100 the number which is increasing, (Bank Account or Student Population).

3) Multiply this answer by 2.1.

4) = Answer

If you remember that 50% is 50 = 1 ( � ), and that 25% is 25 = 1 ( � ), this may help you.
                                                     100   2                                       100   4

I hope that I have helped you.

Les