How do I figure out the percentage increase from $4.00-$5.00
The percentage increase can be calculated as
(New Value - Old Value) / (Old value) * 100%
For example,
The price went up from $5 to $6:
percentage change
= ($6-$5)/$5 *100%
= 1/5 * 100%
= 20%
The change can also be negative, for example, from $32 to $30 (price drop)
percentage change
=($30 - $32) / $32 *100%
=(-2)/32 *100%
=-6.25%
The answer to the given problem ($4 - $5) would be 25%