Question

Tony and Tiffany collect semi-precious stones. At the Rockhound Hut, Tiffany paid $32 for 7 pounds of snowflake obsidian. At The Solid Rock Shop, Tony paid $17 for 5 pounds of the same type of stone. Who made the better buy?

Answer 1

Tony made the better deal. You have to find the lcm which is 5x7 and 7x5. You times 32x5 and 17x7 32x5 is 160 and 17x7 is 119 so Tony made the better deal.

Answer 2

Tony got the better deal