l=10log(1/m)

Question

Loretta had a new muffler installed on her car. The noise level of the engine dropped from 85 decibels to 73 decibels. How many times the minimum intensity of sound detectable by the human ear was the car with the old muffler, if m is defined to be 1?

Answer 1

Using formula L (sound level db) = 10 log(I/m) where I is the sound intensity and m is minimum intensity detectable by human ear.

We have to calculate x=I/m, so 85 = 10 log (x); 8.5 = log(x); x=10^8.5; x=316,227,766