At a rock concert, the engineer decides that the music isn't loud enough. He turns up the amplifiers so that the amplitude of the sound, where you're sitting, increases by 87.0%. By what percentage does the intensity increase? Do not enter unit.
I used the fact that intensity is proportional to amplitude squared.
(A2/A1)^2 = I2/I1
The Attempt at a Solution
85% increase in A, so:
342%-100% = 242%
Answer=242 <-- which is incorrect.
where did I make my mistake?