Without delay, let's solve this. We've got 640 and we will be multiplying it by 344, that is, adding 640 to itself 344 times.
Step 1: 0 + 640 = 640
Step 2: 640 + 640 = 1280
Step 3: 1280 + 640 = 1920
Step 4: 1920 + 640 = 2560
Step 5: 2560 + 640 = 3200
Step 6: 3200 + 640 = 3840
Step 7: 3840 + 640 = 4480
Step 8: 4480 + 640 = 5120
Step 9: 5120 + 640 = 5760
Step 10: 5760 + 640 = 6400
Step 11: 6400 + 640 = 7040
Step 12: 7040 + 640 = 7680
Step 13: 7680 + 640 = 8320
Step 14: 8320 + 640 = 8960
Step 15: 8960 + 640 = 9600
Step 16: 9600 + 640 = 10240
Step 17: 10240 + 640 = 10880
Step 18: 10880 + 640 = 11520
Step 19: 11520 + 640 = 12160
Step 20: 12160 + 640 = 12800
Step 21: 12800 + 640 = 13440
Step 22: 13440 + 640 = 14080
Step 23: 14080 + 640 = 14720
Step 24: 14720 + 640 = 15360
Step 25: 15360 + 640 = 16000
Step 26: 16000 + 640 = 16640
Step 27: 16640 + 640 = 17280
Step 28: 17280 + 640 = 17920
Step 29: 17920 + 640 = 18560
Step 30: 18560 + 640 = 19200
Step 31: 19200 + 640 = 19840
Step 32: 19840 + 640 = 20480
Step 33: 20480 + 640 = 21120
Step 34: 21120 + 640 = 21760
Step 35: 21760 + 640 = 22400
Step 36: 22400 + 640 = 23040
Step 37: 23040 + 640 = 23680
Step 38: 23680 + 640 = 24320
Step 39: 24320 + 640 = 24960
Step 40: 24960 + 640 = 25600
Step 41: 25600 + 640 = 26240
Step 42: 26240 + 640 = 26880
Step 43: 26880 + 640 = 27520
Step 44: 27520 + 640 = 28160
Step 45: 28160 + 640 = 28800
Step 46: 28800 + 640 = 29440
Step 47: 29440 + 640 = 30080
Step 48: 30080 + 640 = 30720
Step 49: 30720 + 640 = 31360
Step 50: 31360 + 640 = 32000
Step 51: 32000 + 640 = 32640
Step 52: 32640 + 640 = 33280
Step 53: 33280 + 640 = 33920
Step 54: 33920 + 640 = 34560
Step 55: 34560 + 640 = 35200
Step 56: 35200 + 640 = 35840
Step 57: 35840 + 640 = 36480
Step 58: 36480 + 640 = 37120
Step 59: 37120 + 640 = 37760
Step 60: 37760 + 640 = 38400
Step 61: 38400 + 640 = 39040
Step 62: 39040 + 640 = 39680
Step 63: 39680 + 640 = 40320
Step 64: 40320 + 640 = 40960
Step 65: 40960 + 640 = 41600
Step 66: 41600 + 640 = 42240
Step 67: 42240 + 640 = 42880
Step 68: 42880 + 640 = 43520
Step 69: 43520 + 640 = 44160
Step 70: 44160 + 640 = 44800
Step 71: 44800 + 640 = 45440
Step 72: 45440 + 640 = 46080
Step 73: 46080 + 640 = 46720
Step 74: 46720 + 640 = 47360
Step 75: 47360 + 640 = 48000
Step 76: 48000 + 640 = 48640
Step 77: 48640 + 640 = 49280
Step 78: 49280 + 640 = 49920
Step 79: 49920 + 640 = 50560
Step 80: 50560 + 640 = 51200
Step 81: 51200 + 640 = 51840
Step 82: 51840 + 640 = 52480
Step 83: 52480 + 640 = 53120
Step 84: 53120 + 640 = 53760
Step 85: 53760 + 640 = 54400
Step 86: 54400 + 640 = 55040
Step 87: 55040 + 640 = 55680
Step 88: 55680 + 640 = 56320
Step 89: 56320 + 640 = 56960
Step 90: 56960 + 640 = 57600
Step 91: 57600 + 640 = 58240
Step 92: 58240 + 640 = 58880
Step 93: 58880 + 640 = 59520
Step 94: 59520 + 640 = 60160
Step 95: 60160 + 640 = 60800
Step 96: 60800 + 640 = 61440
Step 97: 61440 + 640 = 62080
Step 98: 62080 + 640 = 62720
Step 99: 62720 + 640 = 63360
Step 100: 63360 + 640 = 64000
Step 101: 64000 + 640 = 64640
Step 102: 64640 + 640 = 65280
Step 103: 65280 + 640 = 65920
Step 104: 65920 + 640 = 66560
Step 105: 66560 + 640 = 67200
Step 106: 67200 + 640 = 67840
Step 107: 67840 + 640 = 68480
Step 108: 68480 + 640 = 69120
Step 109: 69120 + 640 = 69760
Step 110: 69760 + 640 = 70400
Step 111: 70400 + 640 = 71040
Step 112: 71040 + 640 = 71680
Step 113: 71680 + 640 = 72320
Step 114: 72320 + 640 = 72960
Step 115: 72960 + 640 = 73600
Step 116: 73600 + 640 = 74240
Step 117: 74240 + 640 = 74880
Step 118: 74880 + 640 = 75520
Step 119: 75520 + 640 = 76160
Step 120: 76160 + 640 = 76800
Step 121: 76800 + 640 = 77440
Step 122: 77440 + 640 = 78080
Step 123: 78080 + 640 = 78720
Step 124: 78720 + 640 = 79360
Step 125: 79360 + 640 = 80000
Step 126: 80000 + 640 = 80640
Step 127: 80640 + 640 = 81280
Step 128: 81280 + 640 = 81920
Step 129: 81920 + 640 = 82560
Step 130: 82560 + 640 = 83200
Step 131: 83200 + 640 = 83840
Step 132: 83840 + 640 = 84480
Step 133: 84480 + 640 = 85120
Step 134: 85120 + 640 = 85760
Step 135: 85760 + 640 = 86400
Step 136: 86400 + 640 = 87040
Step 137: 87040 + 640 = 87680
Step 138: 87680 + 640 = 88320
Step 139: 88320 + 640 = 88960
Step 140: 88960 + 640 = 89600
Step 141: 89600 + 640 = 90240
Step 142: 90240 + 640 = 90880
Step 143: 90880 + 640 = 91520
Step 144: 91520 + 640 = 92160
Step 145: 92160 + 640 = 92800
Step 146: 92800 + 640 = 93440
Step 147: 93440 + 640 = 94080
Step 148: 94080 + 640 = 94720
Step 149: 94720 + 640 = 95360
Step 150: 95360 + 640 = 96000
Step 151: 96000 + 640 = 96640
Step 152: 96640 + 640 = 97280
Step 153: 97280 + 640 = 97920
Step 154: 97920 + 640 = 98560
Step 155: 98560 + 640 = 99200
Step 156: 99200 + 640 = 99840
Step 157: 99840 + 640 = 100480
Step 158: 100480 + 640 = 101120
Step 159: 101120 + 640 = 101760
Step 160: 101760 + 640 = 102400
Step 161: 102400 + 640 = 103040
Step 162: 103040 + 640 = 103680
Step 163: 103680 + 640 = 104320
Step 164: 104320 + 640 = 104960
Step 165: 104960 + 640 = 105600
Step 166: 105600 + 640 = 106240
Step 167: 106240 + 640 = 106880
Step 168: 106880 + 640 = 107520
Step 169: 107520 + 640 = 108160
Step 170: 108160 + 640 = 108800
Step 171: 108800 + 640 = 109440
Step 172: 109440 + 640 = 110080
Step 173: 110080 + 640 = 110720
Step 174: 110720 + 640 = 111360
Step 175: 111360 + 640 = 112000
Step 176: 112000 + 640 = 112640
Step 177: 112640 + 640 = 113280
Step 178: 113280 + 640 = 113920
Step 179: 113920 + 640 = 114560
Step 180: 114560 + 640 = 115200
Step 181: 115200 + 640 = 115840
Step 182: 115840 + 640 = 116480
Step 183: 116480 + 640 = 117120
Step 184: 117120 + 640 = 117760
Step 185: 117760 + 640 = 118400
Step 186: 118400 + 640 = 119040
Step 187: 119040 + 640 = 119680
Step 188: 119680 + 640 = 120320
Step 189: 120320 + 640 = 120960
Step 190: 120960 + 640 = 121600
Step 191: 121600 + 640 = 122240
Step 192: 122240 + 640 = 122880
Step 193: 122880 + 640 = 123520
Step 194: 123520 + 640 = 124160
Step 195: 124160 + 640 = 124800
Step 196: 124800 + 640 = 125440
Step 197: 125440 + 640 = 126080
Step 198: 126080 + 640 = 126720
Step 199: 126720 + 640 = 127360
Step 200: 127360 + 640 = 128000
Step 201: 128000 + 640 = 128640
Step 202: 128640 + 640 = 129280
Step 203: 129280 + 640 = 129920
Step 204: 129920 + 640 = 130560
Step 205: 130560 + 640 = 131200
Step 206: 131200 + 640 = 131840
Step 207: 131840 + 640 = 132480
Step 208: 132480 + 640 = 133120
Step 209: 133120 + 640 = 133760
Step 210: 133760 + 640 = 134400
Step 211: 134400 + 640 = 135040
Step 212: 135040 + 640 = 135680
Step 213: 135680 + 640 = 136320
Step 214: 136320 + 640 = 136960
Step 215: 136960 + 640 = 137600
Step 216: 137600 + 640 = 138240
Step 217: 138240 + 640 = 138880
Step 218: 138880 + 640 = 139520
Step 219: 139520 + 640 = 140160
Step 220: 140160 + 640 = 140800
Step 221: 140800 + 640 = 141440
Step 222: 141440 + 640 = 142080
Step 223: 142080 + 640 = 142720
Step 224: 142720 + 640 = 143360
Step 225: 143360 + 640 = 144000
Step 226: 144000 + 640 = 144640
Step 227: 144640 + 640 = 145280
Step 228: 145280 + 640 = 145920
Step 229: 145920 + 640 = 146560
Step 230: 146560 + 640 = 147200
Step 231: 147200 + 640 = 147840
Step 232: 147840 + 640 = 148480
Step 233: 148480 + 640 = 149120
Step 234: 149120 + 640 = 149760
Step 235: 149760 + 640 = 150400
Step 236: 150400 + 640 = 151040
Step 237: 151040 + 640 = 151680
Step 238: 151680 + 640 = 152320
Step 239: 152320 + 640 = 152960
Step 240: 152960 + 640 = 153600
Step 241: 153600 + 640 = 154240
Step 242: 154240 + 640 = 154880
Step 243: 154880 + 640 = 155520
Step 244: 155520 + 640 = 156160
Step 245: 156160 + 640 = 156800
Step 246: 156800 + 640 = 157440
Step 247: 157440 + 640 = 158080
Step 248: 158080 + 640 = 158720
Step 249: 158720 + 640 = 159360
Step 250: 159360 + 640 = 160000
Step 251: 160000 + 640 = 160640
Step 252: 160640 + 640 = 161280
Step 253: 161280 + 640 = 161920
Step 254: 161920 + 640 = 162560
Step 255: 162560 + 640 = 163200
Step 256: 163200 + 640 = 163840
Step 257: 163840 + 640 = 164480
Step 258: 164480 + 640 = 165120
Step 259: 165120 + 640 = 165760
Step 260: 165760 + 640 = 166400
Step 261: 166400 + 640 = 167040
Step 262: 167040 + 640 = 167680
Step 263: 167680 + 640 = 168320
Step 264: 168320 + 640 = 168960
Step 265: 168960 + 640 = 169600
Step 266: 169600 + 640 = 170240
Step 267: 170240 + 640 = 170880
Step 268: 170880 + 640 = 171520
Step 269: 171520 + 640 = 172160
Step 270: 172160 + 640 = 172800
Step 271: 172800 + 640 = 173440
Step 272: 173440 + 640 = 174080
Step 273: 174080 + 640 = 174720
Step 274: 174720 + 640 = 175360
Step 275: 175360 + 640 = 176000
Step 276: 176000 + 640 = 176640
Step 277: 176640 + 640 = 177280
Step 278: 177280 + 640 = 177920
Step 279: 177920 + 640 = 178560
Step 280: 178560 + 640 = 179200
Step 281: 179200 + 640 = 179840
Step 282: 179840 + 640 = 180480
Step 283: 180480 + 640 = 181120
Step 284: 181120 + 640 = 181760
Step 285: 181760 + 640 = 182400
Step 286: 182400 + 640 = 183040
Step 287: 183040 + 640 = 183680
Step 288: 183680 + 640 = 184320
Step 289: 184320 + 640 = 184960
Step 290: 184960 + 640 = 185600
Step 291: 185600 + 640 = 186240
Step 292: 186240 + 640 = 186880
Step 293: 186880 + 640 = 187520
Step 294: 187520 + 640 = 188160
Step 295: 188160 + 640 = 188800
Step 296: 188800 + 640 = 189440
Step 297: 189440 + 640 = 190080
Step 298: 190080 + 640 = 190720
Step 299: 190720 + 640 = 191360
Step 300: 191360 + 640 = 192000
Step 301: 192000 + 640 = 192640
Step 302: 192640 + 640 = 193280
Step 303: 193280 + 640 = 193920
Step 304: 193920 + 640 = 194560
Step 305: 194560 + 640 = 195200
Step 306: 195200 + 640 = 195840
Step 307: 195840 + 640 = 196480
Step 308: 196480 + 640 = 197120
Step 309: 197120 + 640 = 197760
Step 310: 197760 + 640 = 198400
Step 311: 198400 + 640 = 199040
Step 312: 199040 + 640 = 199680
Step 313: 199680 + 640 = 200320
Step 314: 200320 + 640 = 200960
Step 315: 200960 + 640 = 201600
Step 316: 201600 + 640 = 202240
Step 317: 202240 + 640 = 202880
Step 318: 202880 + 640 = 203520
Step 319: 203520 + 640 = 204160
Step 320: 204160 + 640 = 204800
Step 321: 204800 + 640 = 205440
Step 322: 205440 + 640 = 206080
Step 323: 206080 + 640 = 206720
Step 324: 206720 + 640 = 207360
Step 325: 207360 + 640 = 208000
Step 326: 208000 + 640 = 208640
Step 327: 208640 + 640 = 209280
Step 328: 209280 + 640 = 209920
Step 329: 209920 + 640 = 210560
Step 330: 210560 + 640 = 211200
Step 331: 211200 + 640 = 211840
Step 332: 211840 + 640 = 212480
Step 333: 212480 + 640 = 213120
Step 334: 213120 + 640 = 213760
Step 335: 213760 + 640 = 214400
Step 336: 214400 + 640 = 215040
Step 337: 215040 + 640 = 215680
Step 338: 215680 + 640 = 216320
Step 339: 216320 + 640 = 216960
Step 340: 216960 + 640 = 217600
Step 341: 217600 + 640 = 218240
Step 342: 218240 + 640 = 218880
Step 343: 218880 + 640 = 219520
Step 344: 219520 + 640 = 220160

So, 640*344 = 220160