Tony and Tiffany collect semi-precious stones. At the rock hound hut, Tiffany paid $38 for 9 pounds of snowflake obsidian. At the solid rock shop, tony paid $19 for 3 pounds of the same type of the stone. Who made the better buy?

Tiffany made the better buy

Step-by-step explanation:

Based on the information provided within the question it can be said that Tiffany made the better buy in this scenario. Mainly because Tiffany paid a less amount per pound than Tony did. This can be calculated by dividing the total amount each paid by the total amount each of them received, like so ...

Tiffany: $38 / 9 = $4.22 per pound

Tony: $19 / 3 = $6.33 per pound

Therefore we can see that Tiffany paid $4.22 per pound and Tony paid $6.33 per pound a whole $2.11 more than Tiffany, thus making Tiffany purchase the better buy.