How do you find the percent change given the original number is 48 and new number is 60?

1 Answer
Feb 15, 2017

41.23%

Explanation:

Goes from 4860

So this is an increase of 6040=20

We express this as a change in relation to the original price. So the change expressed as a fraction of the original price is :

+2048

Using first principles to explain where the ×100
in the shortcut method comes from

2048×1 = 2048×100100 = 20×10048×1100

But 1100 is the same as % giving:

=20×10048%

Writing this as in the shortcut method we have:

=(2048×100)%=41.6¯6%
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Foot note

The bar over the last 6 indicates that the value 6 repeats for ever.

It is really helpful to remember that 0.333¯3 is the same as 13

So 0.666¯6 is the same as 2×13=23

Thus: 41.6¯6=4123%