Luis is making chocolate chip cookies. The recipe calls for ; cup of almonds for every :
a cup of
chocolate chips. If Luis uses 3 cups of chocolate chips, how many cups of almonds will he need? Round to the nearest tenth.
If the recipe calls for ; cup of almonds for every 1 cup of chocolate chips, then for 3 cups of chocolate chips, Luis will need 3 x ; cups of almonds.
Therefore, Luis will need 3 x ; = 1.5 cups of almonds. Rounded to the nearest tenth, he will need 1.5 cups of almonds. Answer: \boxed{1.5}.