Answer:
15%
If you get 7.5 from 75 by moving over 1 decimal place then divide 112.50 by 7.5 you get 15 percent as your answer
The midpoint of the range of frequencies given is:
midpoint = (82.4 +
659.2) / 2 = 370.8 Hertz
Then the difference from midpoint to the other end is:
370.8 - 83.4 = 288.4 Hertz
Therefore the inequality formula is
|f - 370.8| <= 288.4