Answer:
21
Step-by-step explanation:
there are 2 1s.
1 + 1 = 2
we take those original 2 and multiply them to make 4.
now were at step 3
3 + 4 = 7
now step 4, the last step was 3, whats 4-3? 1!
now we take 4-1=3
now, we take
7 x 3 = 21!!!!!