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## Homework Statement

A race car is traveling towards you and you hear a sound a frequency 3895.9 Hz. Then the car shoots by you. As the car moves away you hear a frequency of 2574.6 Hz. What is the speed of the car? Assume the temperature of the air is 20 degrees Celsius.

## Homework Equations

F_o = frequency of observer. Fs = frequency of source.

A source moving towards a stationary observer.

F_o = Fs1( 1 / (1-vs/v)

A source moving away from a stationary observer.

F_o = Fs2( 1 / (1+vs/v)

## The Attempt at a Solution

So I thought that I could set the two equal and solve for vs but this is not a good plan because It doesn't simplify nice. At least my attempts didn't.

Fs1( 1 / (1-vs/v) = Fs2( 1 / (1+vs/v)

I'm actually confused on this because I thought the question was giving me the frequency the observer hears which is F_o ??

I'm lost please point me in right direction.