"Eu tenho uma lâmpada que é mais velha do que a da minha casa."

Translation: I have a lamp that is older than the one at my house.

[legatrix]

...Than the one at my house.

[Lisa11449]

Why "da"? I would have translated "NA minha casa"...

[Endverbraucher]

I have a lightbulb that is older than that of my house.
Accept it!
It's a stupid sentence, but it's a valid translation.