43 × 16 + 16 × 19 = 688 + 304 = 992 → primul mod
→ aplic distributivitatea ca proprietate a inmultirii
= 16 × ( 43 + 19 ) = 16 × 62 = 992 → al doilea mod
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51 × 40 - 32 × 40 = 2 040 - 1 280 = 760 → primul mod
= 40 × ( 51 - 32 ) = 40 × 19 = 760 → al doilea mod
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145 × 17 - 17 × 45 = 2 465 - 765 = 1 700 → primul mod
= 17 × ( 145 - 45 ) = 17 × 100 = 1 700 → al doilea mod
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270 × 30 - 270 × 25 = 8 100 - 6 750 = 1 350 → primul mod
= 270 × ( 30 - 25 ) = 270 × 5 = 1 350 → al doilea mod