Mathematical Fallacy 2 Provoke deeper thinking

Write an Error in the proof in the comment box

[jothilingamtr]

For any multiplication we have to use the same units on both side of the equation. Here one side feet is taken and the other side inches are taken, which will give wrong answer. If we take meter 1 meter x i meter = 100 cm x 100 cm will be equals to one meter = 10, 000 cms, which is wrong.
if we take l meter length and one meter breadth then 10, 000 sq.cm will be ok. So the basic mistake is taking two unequal units for multiplication