Question

The price of a notebook was

Answer 1

Old price: p1 = $ 3.90;

New price: p2 = $ 3.40.


The percentual decrease is given by

d(%) = [ (p2 - p1) / p1 ] * 100 %

d(%) = [ (3.40 - 3.90) / 3.90 ] * 100 %

d(%) = [ - 0.50 / 3.90 ] * 100 %

d(%) = - 0.128 * 100 %

d(%) = - 12.8 % (approximately)


So the price fell 12.8 % approximately.


I hope this helps. =)