Alright, let's solve this math problem step by step. First, we have the number 690. Next, we see the multiplication sign, which means we need to multiply something. And what are we multiplying it by? We multiply it by 157. So, we're going to take the number 690 and add it to itself 157 times.
Step 1: 0 + 690 = 690
Step 2: 690 + 690 = 1380
Step 3: 1380 + 690 = 2070
Step 4: 2070 + 690 = 2760
Step 5: 2760 + 690 = 3450
Step 6: 3450 + 690 = 4140
Step 7: 4140 + 690 = 4830
Step 8: 4830 + 690 = 5520
Step 9: 5520 + 690 = 6210
Step 10: 6210 + 690 = 6900
Step 11: 6900 + 690 = 7590
Step 12: 7590 + 690 = 8280
Step 13: 8280 + 690 = 8970
Step 14: 8970 + 690 = 9660
Step 15: 9660 + 690 = 10350
Step 16: 10350 + 690 = 11040
Step 17: 11040 + 690 = 11730
Step 18: 11730 + 690 = 12420
Step 19: 12420 + 690 = 13110
Step 20: 13110 + 690 = 13800
Step 21: 13800 + 690 = 14490
Step 22: 14490 + 690 = 15180
Step 23: 15180 + 690 = 15870
Step 24: 15870 + 690 = 16560
Step 25: 16560 + 690 = 17250
Step 26: 17250 + 690 = 17940
Step 27: 17940 + 690 = 18630
Step 28: 18630 + 690 = 19320
Step 29: 19320 + 690 = 20010
Step 30: 20010 + 690 = 20700
Step 31: 20700 + 690 = 21390
Step 32: 21390 + 690 = 22080
Step 33: 22080 + 690 = 22770
Step 34: 22770 + 690 = 23460
Step 35: 23460 + 690 = 24150
Step 36: 24150 + 690 = 24840
Step 37: 24840 + 690 = 25530
Step 38: 25530 + 690 = 26220
Step 39: 26220 + 690 = 26910
Step 40: 26910 + 690 = 27600
Step 41: 27600 + 690 = 28290
Step 42: 28290 + 690 = 28980
Step 43: 28980 + 690 = 29670
Step 44: 29670 + 690 = 30360
Step 45: 30360 + 690 = 31050
Step 46: 31050 + 690 = 31740
Step 47: 31740 + 690 = 32430
Step 48: 32430 + 690 = 33120
Step 49: 33120 + 690 = 33810
Step 50: 33810 + 690 = 34500
Step 51: 34500 + 690 = 35190
Step 52: 35190 + 690 = 35880
Step 53: 35880 + 690 = 36570
Step 54: 36570 + 690 = 37260
Step 55: 37260 + 690 = 37950
Step 56: 37950 + 690 = 38640
Step 57: 38640 + 690 = 39330
Step 58: 39330 + 690 = 40020
Step 59: 40020 + 690 = 40710
Step 60: 40710 + 690 = 41400
Step 61: 41400 + 690 = 42090
Step 62: 42090 + 690 = 42780
Step 63: 42780 + 690 = 43470
Step 64: 43470 + 690 = 44160
Step 65: 44160 + 690 = 44850
Step 66: 44850 + 690 = 45540
Step 67: 45540 + 690 = 46230
Step 68: 46230 + 690 = 46920
Step 69: 46920 + 690 = 47610
Step 70: 47610 + 690 = 48300
Step 71: 48300 + 690 = 48990
Step 72: 48990 + 690 = 49680
Step 73: 49680 + 690 = 50370
Step 74: 50370 + 690 = 51060
Step 75: 51060 + 690 = 51750
Step 76: 51750 + 690 = 52440
Step 77: 52440 + 690 = 53130
Step 78: 53130 + 690 = 53820
Step 79: 53820 + 690 = 54510
Step 80: 54510 + 690 = 55200
Step 81: 55200 + 690 = 55890
Step 82: 55890 + 690 = 56580
Step 83: 56580 + 690 = 57270
Step 84: 57270 + 690 = 57960
Step 85: 57960 + 690 = 58650
Step 86: 58650 + 690 = 59340
Step 87: 59340 + 690 = 60030
Step 88: 60030 + 690 = 60720
Step 89: 60720 + 690 = 61410
Step 90: 61410 + 690 = 62100
Step 91: 62100 + 690 = 62790
Step 92: 62790 + 690 = 63480
Step 93: 63480 + 690 = 64170
Step 94: 64170 + 690 = 64860
Step 95: 64860 + 690 = 65550
Step 96: 65550 + 690 = 66240
Step 97: 66240 + 690 = 66930
Step 98: 66930 + 690 = 67620
Step 99: 67620 + 690 = 68310
Step 100: 68310 + 690 = 69000
Step 101: 69000 + 690 = 69690
Step 102: 69690 + 690 = 70380
Step 103: 70380 + 690 = 71070
Step 104: 71070 + 690 = 71760
Step 105: 71760 + 690 = 72450
Step 106: 72450 + 690 = 73140
Step 107: 73140 + 690 = 73830
Step 108: 73830 + 690 = 74520
Step 109: 74520 + 690 = 75210
Step 110: 75210 + 690 = 75900
Step 111: 75900 + 690 = 76590
Step 112: 76590 + 690 = 77280
Step 113: 77280 + 690 = 77970
Step 114: 77970 + 690 = 78660
Step 115: 78660 + 690 = 79350
Step 116: 79350 + 690 = 80040
Step 117: 80040 + 690 = 80730
Step 118: 80730 + 690 = 81420
Step 119: 81420 + 690 = 82110
Step 120: 82110 + 690 = 82800
Step 121: 82800 + 690 = 83490
Step 122: 83490 + 690 = 84180
Step 123: 84180 + 690 = 84870
Step 124: 84870 + 690 = 85560
Step 125: 85560 + 690 = 86250
Step 126: 86250 + 690 = 86940
Step 127: 86940 + 690 = 87630
Step 128: 87630 + 690 = 88320
Step 129: 88320 + 690 = 89010
Step 130: 89010 + 690 = 89700
Step 131: 89700 + 690 = 90390
Step 132: 90390 + 690 = 91080
Step 133: 91080 + 690 = 91770
Step 134: 91770 + 690 = 92460
Step 135: 92460 + 690 = 93150
Step 136: 93150 + 690 = 93840
Step 137: 93840 + 690 = 94530
Step 138: 94530 + 690 = 95220
Step 139: 95220 + 690 = 95910
Step 140: 95910 + 690 = 96600
Step 141: 96600 + 690 = 97290
Step 142: 97290 + 690 = 97980
Step 143: 97980 + 690 = 98670
Step 144: 98670 + 690 = 99360
Step 145: 99360 + 690 = 100050
Step 146: 100050 + 690 = 100740
Step 147: 100740 + 690 = 101430
Step 148: 101430 + 690 = 102120
Step 149: 102120 + 690 = 102810
Step 150: 102810 + 690 = 103500
Step 151: 103500 + 690 = 104190
Step 152: 104190 + 690 = 104880
Step 153: 104880 + 690 = 105570
Step 154: 105570 + 690 = 106260
Step 155: 106260 + 690 = 106950
Step 156: 106950 + 690 = 107640
Step 157: 107640 + 690 = 108330

So, 690*157 = 108330