Explaining bra sizing to boys?

Ladies, I was trying to explain bra sizing to my other half the other night and despite his best efforts, the poor thing was confused after the first 30 seconds.
I have no idea how to explain it to him. It even starts to spin me around if I think about it for too long.
Feel free to share your opinions and funny stories :)
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+1 y
My friend is a plump girl, much taller than me, and is several cup sizes below me. Our bra sizes are completely different, and looking at these graphs and going by what I've always been told, my bras should be bigger because I have a higher cup size, but her boobs are way bigger than mine. I look like I've got two mosquito bites when next to her.
Explaining bra sizing to boys?
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