Percentage Change Formula

When there is a change in values, to know the percent change in the values, percent change formula is used. Sometimes to know the discounts change, the change in prices of products or income, percentage change formula comes in handy.  It is expressed in percentage, it is the change in new value with respect to the old value.  The change in value is divided by the original value and then multiplied by 100.

Percentage change formula is

\[\large Percentage\;Change=\frac{Old\;Value-New\;Value}{Old\;Value}\times 100\]

Solved example

Question: What is the percentage change in the weight of Krishna, if he had decreased to 77 kg from 82 kg?


Using the formula: $Percentage\;Change=\frac{Old\;Value-New\;Value}{Old\;Value}\times 100$

$Percentage\;Change=\frac{82-77}{77}\times 100$

= 6.4

Hence the percent change in his weight = 6.4%

Practise This Question

Nucleus of mass number A, originally at rest, emits an α -particle with speed v. The daughter nucleus recoils with a speed