This question is incomplete, the complete question is;
In the experiment, a meter is hooked up to a speaker to monitor the amplitude of the received sound. Suppose the background signal level is 13 mV, the signal is 91 mV with no attenuator and is 25 mV with an attenuator in place. Calculate pt /pi
Answer: the pt/pi is 15.3846%
Step-by-step explanation:
Given that;
Background = 13 mV
corrected signal = 91 mV - 13 mV = 78 mV
with attenuator = 25 mV - 13 mV = 12 mV
pt/pi = ?
so pt/pi = 12/78 × 100
= 15.3846%
Therefore the pt/pi is 15.3846%