Give the step-by-step reasoning process and then the final answer. Ali has a small flower shop. He sold 4 flowers on Monday, 8 flowers on Tuesday and on Friday, he sold double the number of flowers he sold on Monday. How many flowers does Ali sell?
Combining Tuesday and Monday, Ali sold 4 + 8 = 12 flowers. On Friday, he sold 2 * 4 = 8 flowers. Altogether, Ali sold 12 + 8 = 20 flowers.
The final answer: 20.