OK, let's work through this together. We're starting with 720 and we're going to multiply it by 26, which means we add 720 to itself 26 times.
Step 1: 0 + 720 = 720
Step 2: 720 + 720 = 1440
Step 3: 1440 + 720 = 2160
Step 4: 2160 + 720 = 2880
Step 5: 2880 + 720 = 3600
Step 6: 3600 + 720 = 4320
Step 7: 4320 + 720 = 5040
Step 8: 5040 + 720 = 5760
Step 9: 5760 + 720 = 6480
Step 10: 6480 + 720 = 7200
Step 11: 7200 + 720 = 7920
Step 12: 7920 + 720 = 8640
Step 13: 8640 + 720 = 9360
Step 14: 9360 + 720 = 10080
Step 15: 10080 + 720 = 10800
Step 16: 10800 + 720 = 11520
Step 17: 11520 + 720 = 12240
Step 18: 12240 + 720 = 12960
Step 19: 12960 + 720 = 13680
Step 20: 13680 + 720 = 14400
Step 21: 14400 + 720 = 15120
Step 22: 15120 + 720 = 15840
Step 23: 15840 + 720 = 16560
Step 24: 16560 + 720 = 17280
Step 25: 17280 + 720 = 18000
Step 26: 18000 + 720 = 18720

So, 720*26 = 18720