Let's roll up our sleeves and solve this. We have 770 and we're going to multiply it by 7, essentially adding 770 to itself 7 times.
Step 1: 0 + 770 = 770
Step 2: 770 + 770 = 1540
Step 3: 1540 + 770 = 2310
Step 4: 2310 + 770 = 3080
Step 5: 3080 + 770 = 3850
Step 6: 3850 + 770 = 4620
Step 7: 4620 + 770 = 5390

So, 770*7 = 5390