Due to the installation of a muffler, the noise level of an engine decreased from 88 to 72 decibels. Find the percent decrease in the intensity of the noise as a result of the installation of the muffler.
Use the following information for determining sound intensity. The number of decibels β of a sound with an intensity of I watts per square meter is given by β = 10 log(I/I0), where I0 is an intensity of 10-12 watt per square meter, corresponding roughly to the faintest sound that can be heard by the human ear.