Answer:
18
Step-by-step explanation:
3*5=15
Therefore, every time she completed 3 pages that was a mark down.
3= 1/6 12=4/6
6=2/6 15=5/6
9=3/6 18=6/6 or 1 whole
I think A. Reflexive Property but if I am wrong, I am so sorry
because 6 + 1 is is not subtracting or multiplying
Hope this helps