Becca has a biscuit recipe that uses 2/3 of a tablespoon of salt for every 3/4 of a cup of flour. in order to have enough biscuits for her family that is visiting, becca is making a batch of biscuits using 3 cups of flour and how many tablespoons of salt will she need

 2/3   -  3/4
   x    -  3

x= (2/3 * 3) / (3/4) = 2 * (4/3) = 8/3 = 2 and 2/3 of tablespoon of salt  

In your question if Becca uses 3/4 cup of flour to her biscuit, she uses 2/3 tablespoon of salt and the batch of biscuit that she made uses 3 cup of flours. In finding how much tablespoon of salt use in a 3 cups of flour, you must first find the total cup of flour which 4 and the possible total table spoon of salt is 3. So by calculating the answer is 2 and 2/3 tablespoon of salt