OK, let's work through this together. We're starting with 170 and we're going to multiply it by 11, which means we add 170 to itself 11 times.
Step 1: 0 + 170 = 170
Step 2: 170 + 170 = 340
Step 3: 340 + 170 = 510
Step 4: 510 + 170 = 680
Step 5: 680 + 170 = 850
Step 6: 850 + 170 = 1020
Step 7: 1020 + 170 = 1190
Step 8: 1190 + 170 = 1360
Step 9: 1360 + 170 = 1530
Step 10: 1530 + 170 = 1700
Step 11: 1700 + 170 = 1870

So, 170*11 = 1870