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# CMTimebaseGetEffectiveRate(_:)

Returns the effective rate of a timebase, which combines its rate with the rates of all its host timebases.

```
func CMTimebaseGetEffectiveRate(_ timebase: CMTimebase) -> Float64
```

## Discussion

Calling `CMTimebaseGetEffectiveRate(timebase)` is equivalent to calling `CMSyncGetRelativeRate(timebase, CMTimebaseGetUltimateMasterClock(timebase))`.

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