OK, let's work through this together. We're starting with 867 and we're going to multiply it by 10, which means we add 867 to itself 10 times.
Step 1: 0 + 867 = 867
Step 2: 867 + 867 = 1734
Step 3: 1734 + 867 = 2601
Step 4: 2601 + 867 = 3468
Step 5: 3468 + 867 = 4335
Step 6: 4335 + 867 = 5202
Step 7: 5202 + 867 = 6069
Step 8: 6069 + 867 = 6936
Step 9: 6936 + 867 = 7803
Step 10: 7803 + 867 = 8670

So, 867*10 = 8670