Answer:
12
Step-by-step explanation:
Since we know that 9 is 3/4 of what she needs you would divide 9 by 3 so we know how much 1/4 of a cup is worth.
(9/3=3) now we know she needs 3 cups of flour for 1/4 of the expression. Now we multiply 3 by 4 so we can get the answer.
(3x4=12)
Molly needs 12 cups of flour to make bread.
Hope this helps :)