The ruling on exchanging macaroni for vermicelli in unequal amounts

The questioner:
May Allah reward you. This questioner says: I receive quantities of macaroni at my house from some of my friends, and my children do not like macaroni; rather, they like vermicelli. So I go to the grocer and exchange ten bags of macaroni for seven bags of vermicelli.

The Shaykh:
No, this is riba (usury or interest). This is riba. It is not permissible. This is food, and it is not permissible to increase in its kind. But if the kind differs—if the vermicelli is not of the same kind as the macaroni—it is permissible. If these kinds differ, sell however you wish, provided it is hand-to-hand.

The presenter:
May Allah reward you

The questioner:
Honorable Shaykh, this questioner asks: What is the ruling on buying?

The Shaykh:
If their base is the same, increasing is not permissible. But if their base is different, there is no harm. For example, wheat with barley; this is different. Yes.