Question

unit 2 exam
listen
a song starts with a note tuned to 220 hz.
what is the frequency of the perfect fourth above the given note, rounded to the nearest whole number?
367 hz
165 hz
293 hz
275 hz

Explanation:

Step1: Recall frequency ratio for perfect fourth

The frequency ratio for a perfect - fourth interval is $\frac{4}{3}$.

Step2: Calculate the frequency of the perfect fourth

Given the base frequency $f_0 = 220$ Hz. The frequency of the perfect fourth $f$ is $f=f_0\times\frac{4}{3}$. So, $f = 220\times\frac{4}{3}=\frac{880}{3}\approx293.33$ Hz.

Step3: Round to the nearest whole number

Rounding $293.33$ Hz to the nearest whole number gives $293$ Hz.

Answer:

293 Hz