If You Can Hear These Noises You're Probably Under 25

If you are aged 25 or over you should not be able to hear the mosquito tone, which is a noise above 17.4kHz.

This is down to age-induced hearing loss, which happens as the hairs in your ear wear down as they are exposed to sound throughout your lifetime.

For the majority of us this will happen by the time we hit our mid-twenties and from then will continue to deteriorate. 

But this video below will be able to tell you just what age your hearing is:

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