Hello! I am confused about 1.11:

In the first solution I did, I got 61!=7, in the second (easier) method I used, I got the correct answer. Can you tell me what is wrong 

The solution on the Post-it note is the second (correct) solution, but the one on the binder paper is the first solution I did. I cannot see where it is wrong.

Can you tell me where the first solution is wrong??

Thanks!

Tina Jin