Percentages are Reversible

​
percentage
8
value
25
8%
of
25
is
2.
25%
of
8
is
2.
Arithmetic multiplication is commutative,
a×b=b×a
. As a consequence, values in a percentage calculation are reversible. When doing such calculations mentally, sometimes it is easier to swap the percentage and value.

Permanent Citation

Ed Pegg Jr
​
​"Percentages are Reversible"​
​http://demonstrations.wolfram.com/PercentagesAreReversible/​
​Wolfram Demonstrations Project​
​Published: July 24, 2020