Let's get this math done. We have 85 and we're going to multiply it by 13. This is the same as taking 85 and adding it to itself 13 times.
Step 1: 0 + 85 = 85
Step 2: 85 + 85 = 170
Step 3: 170 + 85 = 255
Step 4: 255 + 85 = 340
Step 5: 340 + 85 = 425
Step 6: 425 + 85 = 510
Step 7: 510 + 85 = 595
Step 8: 595 + 85 = 680
Step 9: 680 + 85 = 765
Step 10: 765 + 85 = 850
Step 11: 850 + 85 = 935
Step 12: 935 + 85 = 1020
Step 13: 1020 + 85 = 1105

So, 85*13 = 1105