Multiplication Level 30: 4d x 4d (full range mastery). multi-digit window train. 1. Left Edge7865 times 92871. Left EdgeUse the highlighted left edge pair.7865times92877x9632 pairs3 pairs4 pairs3 pairs2 pairs5x7Active multiplication train windowraw windowsraw -> 63 | _ | _ | _ | _ | _ | _Use the highlighted left edge pair. Carry waits for settle.2. 2-Pair Window2. 2-Pair WindowAdd both highlighted pairs.7865times92877x9632 pairs863 pairs4 pairs3 pairs2 pairs5x7Active multiplication train windowraw windowsraw -> 63 | 86 | _ | _ | _ | _ | _Add both highlighted pairs. Carry waits for settle.3. 3-Pair Window3. 3-Pair WindowAdd all 3 highlighted pairs.7865times92877x9632 pairs863 pairs1264 pairs3 pairs2 pairs5x7Active multiplication train windowraw windowsraw -> 63 | 86 | 126 | _ | _ | _ | _Add all 3 highlighted pairs. Carry waits for settle.4. 4-Pair Center4. 4-Pair CenterAdd all 4 highlighted pairs.7865times92877x9632 pairs863 pairs1264 pairs1703 pairs2 pairs5x7Active multiplication train windowraw windowsraw -> 63 | 86 | 126 | 170 | _ | _ | _Add all 4 highlighted pairs. Carry waits for settle.5. 3-Pair Right Window5. 3-Pair Right WindowAdd all 3 highlighted pairs.7865times92877x9632 pairs863 pairs1264 pairs1703 pairs1142 pairs5x7Active multiplication train windowraw windowsraw -> 63 | 86 | 126 | 170 | 114 | _ | _Add all 3 highlighted pairs. Carry waits for settle.6. 2-Pair Right Window6. 2-Pair Right WindowAdd both highlighted pairs.7865times92877x9632 pairs863 pairs1264 pairs1703 pairs1142 pairs825x7Active multiplication train windowraw windowsraw -> 63 | 86 | 126 | 170 | 114 | 82 | _Add both highlighted pairs. Carry waits for settle.7. 1-Pair Right Edge7. 1-Pair Right EdgeUse the highlighted right edge pair.7865times92877x9632 pairs863 pairs1264 pairs1703 pairs1142 pairs825x735Active multiplication train windowraw windowsraw -> 63 | 86 | 126 | 170 | 114 | 82 | 35Use the highlighted right edge pair. Carry waits for settle.8. Settle strip8. Settle stripSettle once.Keep ones; carry moves left.raw windows63 | 86 | 126 | 170 | 114 | 82 | 35settled strip73 | 0 | 4 | 2 | 2 | 5 | 5Final multiplication answer63 | 86 | 126 | 170 | 114 | 82 | 35 -> 73042255.