Answer:
20 cookies
Explanation:
Mary can make 15 cookies with 3 scoops of flour. Using an equation, we can see how many cookies she can make for each scoop of flour: 15 ÷ 3= 5. So, this means that for each scoop of flour, Mary can make 5 cookies. If she has 4 scoops of flour, we now just need to multiply 4 by the number 5 to see how many she can make now: 4 × 5= 20. From this equation we can see that Mary can make 20 cookies. This is our answer!