Half of 34 cups is 17 cups. If you mean half of 3/4 is 3/8 of a cup. You can use 1/8 of a cup three times. If you don't have a 1/8 of a cup use 1/4 cup plus two tablespoons.
http://answers.ask.com/Reference/Other/what_is_hal...

If you think to 3,4 US cups  402,22 mL.
http://wiki.answers.com/Q/What_is_half_of_3_and_4_...

You may need to add half of 3/4 cup sugar to a recipe because you're cutting the recipe in half, or because you know a recipe calls for much more sugar than you prefer. Plastic and
http://www.ehow.com/how_5606673_measurehalf3_4c...

Half of 3/4 of a cup is equal to 3/8 of a cup, or 6 tablespoons. ChaCha again soon!
http://www.chacha.com/question/whatishalfof3%2...
