Alright, let's solve this math problem step by step. First, we have the number 900. Next, we see the multiplication sign, which means we need to multiply something. And what are we multiplying it by? We multiply it by 131. So, we're going to take the number 900 and add it to itself 131 times.
Step 1: 0 + 900 = 900
Step 2: 900 + 900 = 1800
Step 3: 1800 + 900 = 2700
Step 4: 2700 + 900 = 3600
Step 5: 3600 + 900 = 4500
Step 6: 4500 + 900 = 5400
Step 7: 5400 + 900 = 6300
Step 8: 6300 + 900 = 7200
Step 9: 7200 + 900 = 8100
Step 10: 8100 + 900 = 9000
Step 11: 9000 + 900 = 9900
Step 12: 9900 + 900 = 10800
Step 13: 10800 + 900 = 11700
Step 14: 11700 + 900 = 12600
Step 15: 12600 + 900 = 13500
Step 16: 13500 + 900 = 14400
Step 17: 14400 + 900 = 15300
Step 18: 15300 + 900 = 16200
Step 19: 16200 + 900 = 17100
Step 20: 17100 + 900 = 18000
Step 21: 18000 + 900 = 18900
Step 22: 18900 + 900 = 19800
Step 23: 19800 + 900 = 20700
Step 24: 20700 + 900 = 21600
Step 25: 21600 + 900 = 22500
Step 26: 22500 + 900 = 23400
Step 27: 23400 + 900 = 24300
Step 28: 24300 + 900 = 25200
Step 29: 25200 + 900 = 26100
Step 30: 26100 + 900 = 27000
Step 31: 27000 + 900 = 27900
Step 32: 27900 + 900 = 28800
Step 33: 28800 + 900 = 29700
Step 34: 29700 + 900 = 30600
Step 35: 30600 + 900 = 31500
Step 36: 31500 + 900 = 32400
Step 37: 32400 + 900 = 33300
Step 38: 33300 + 900 = 34200
Step 39: 34200 + 900 = 35100
Step 40: 35100 + 900 = 36000
Step 41: 36000 + 900 = 36900
Step 42: 36900 + 900 = 37800
Step 43: 37800 + 900 = 38700
Step 44: 38700 + 900 = 39600
Step 45: 39600 + 900 = 40500
Step 46: 40500 + 900 = 41400
Step 47: 41400 + 900 = 42300
Step 48: 42300 + 900 = 43200
Step 49: 43200 + 900 = 44100
Step 50: 44100 + 900 = 45000
Step 51: 45000 + 900 = 45900
Step 52: 45900 + 900 = 46800
Step 53: 46800 + 900 = 47700
Step 54: 47700 + 900 = 48600
Step 55: 48600 + 900 = 49500
Step 56: 49500 + 900 = 50400
Step 57: 50400 + 900 = 51300
Step 58: 51300 + 900 = 52200
Step 59: 52200 + 900 = 53100
Step 60: 53100 + 900 = 54000
Step 61: 54000 + 900 = 54900
Step 62: 54900 + 900 = 55800
Step 63: 55800 + 900 = 56700
Step 64: 56700 + 900 = 57600
Step 65: 57600 + 900 = 58500
Step 66: 58500 + 900 = 59400
Step 67: 59400 + 900 = 60300
Step 68: 60300 + 900 = 61200
Step 69: 61200 + 900 = 62100
Step 70: 62100 + 900 = 63000
Step 71: 63000 + 900 = 63900
Step 72: 63900 + 900 = 64800
Step 73: 64800 + 900 = 65700
Step 74: 65700 + 900 = 66600
Step 75: 66600 + 900 = 67500
Step 76: 67500 + 900 = 68400
Step 77: 68400 + 900 = 69300
Step 78: 69300 + 900 = 70200
Step 79: 70200 + 900 = 71100
Step 80: 71100 + 900 = 72000
Step 81: 72000 + 900 = 72900
Step 82: 72900 + 900 = 73800
Step 83: 73800 + 900 = 74700
Step 84: 74700 + 900 = 75600
Step 85: 75600 + 900 = 76500
Step 86: 76500 + 900 = 77400
Step 87: 77400 + 900 = 78300
Step 88: 78300 + 900 = 79200
Step 89: 79200 + 900 = 80100
Step 90: 80100 + 900 = 81000
Step 91: 81000 + 900 = 81900
Step 92: 81900 + 900 = 82800
Step 93: 82800 + 900 = 83700
Step 94: 83700 + 900 = 84600
Step 95: 84600 + 900 = 85500
Step 96: 85500 + 900 = 86400
Step 97: 86400 + 900 = 87300
Step 98: 87300 + 900 = 88200
Step 99: 88200 + 900 = 89100
Step 100: 89100 + 900 = 90000
Step 101: 90000 + 900 = 90900
Step 102: 90900 + 900 = 91800
Step 103: 91800 + 900 = 92700
Step 104: 92700 + 900 = 93600
Step 105: 93600 + 900 = 94500
Step 106: 94500 + 900 = 95400
Step 107: 95400 + 900 = 96300
Step 108: 96300 + 900 = 97200
Step 109: 97200 + 900 = 98100
Step 110: 98100 + 900 = 99000
Step 111: 99000 + 900 = 99900
Step 112: 99900 + 900 = 100800
Step 113: 100800 + 900 = 101700
Step 114: 101700 + 900 = 102600
Step 115: 102600 + 900 = 103500
Step 116: 103500 + 900 = 104400
Step 117: 104400 + 900 = 105300
Step 118: 105300 + 900 = 106200
Step 119: 106200 + 900 = 107100
Step 120: 107100 + 900 = 108000
Step 121: 108000 + 900 = 108900
Step 122: 108900 + 900 = 109800
Step 123: 109800 + 900 = 110700
Step 124: 110700 + 900 = 111600
Step 125: 111600 + 900 = 112500
Step 126: 112500 + 900 = 113400
Step 127: 113400 + 900 = 114300
Step 128: 114300 + 900 = 115200
Step 129: 115200 + 900 = 116100
Step 130: 116100 + 900 = 117000
Step 131: 117000 + 900 = 117900

So, 900*131 = 117900