OK, let's work through this together. We're starting with 780 and we're going to multiply it by 6, which means we add 780 to itself 6 times.
Step 1: 0 + 780 = 780
Step 2: 780 + 780 = 1560
Step 3: 1560 + 780 = 2340
Step 4: 2340 + 780 = 3120
Step 5: 3120 + 780 = 3900
Step 6: 3900 + 780 = 4680

So, 780*6 = 4680