Final answer:
To make the dough for 9 small pizzas with each using 1/13 cup of flour, the cook needs a total of 9/13 cups of flour, which is in simplest form.
Step-by-step explanation:
The question asks to calculate how much flour is needed for making 9 small pizzas, each requiring 1/13 cup of flour. To find the total amount of flour needed, multiply the amount of flour needed for one pizza by the number of pizzas.
1/13 cup of flour per pizza × 9 pizzas = 9/13 cups of flour in total.
Since 9/13 is already in its simplest form, the cook needs 9/13 cups of flour to make the dough for all 9 small pizzas.