YOU SAID:

I went to the supermarket and bought fifteen pounds of potatoes

INTO JAPANESE

私はスーパーに行き、15ポンドのジャガイモを買いました

BACK INTO ENGLISH

I went to the supermarket and bought a 15 pound potato

INTO JAPANESE

スーパーに行って15ポンドのジャガイモを買いました

BACK INTO ENGLISH

I went to the supermarket and bought a 15 pound potato