Sound Intensity Problem of 3 Machines

[dvolpe]

Homework Statement

In a factory, 3 machines produce noise with intensity levels of 76 dB, 82 dB, and 85 dB. With all three running, what is the intensity level?

Homework Equations

B = 10 log (I/Io)

The Attempt at a Solution

B = 10 log (10e7.6 + 10e8.2 + 10e8.5)

I do not know how to evaluate this! Help please!

 

[dvolpe]

Solved - just plug numbers into calculator for exponents!