Answer: 19 ¹/₂ cups of purple paint
Explanation:
First find out the quantity of purple pain that she has:
= 3/4 + 3/4
= 6/4 cups of paint.
If she mixes 13 batches, the cups of purple paint she will have will be the original number multiplied by 13
= 6/4 * 13
= 78/4
= 19 ¹/₂ cups of purple paint