Вопрос:

*2* - 1*7 = 805

Смотреть решения всех заданий с листа

Ответ:

Let the first number be $$A2B$$ and the second number be $$1C7$$. The subtraction is $$A2B - 1C7 = 805$$.
From the units digit, $$B - 7$$ must end in 5. This means $$B = 2$$ (since $$12 - 7 = 5$$).
From the tens digit, $$2 - C$$ (with a potential borrow from $$A$$) must result in 0. If we borrowed for the units digit, it would be $$1 - C$$ ending in 0, so $$C=1$$. If we didn't borrow, $$2 - C = 0$$, so $$C=2$$.
From the hundreds digit, $$A - 1$$ (with a potential borrow) must result in 8.
Case 1: $$C=1$$. No borrow from 2. $$A - 1 = 8$$, so $$A=9$$. The numbers are $$922 - 117 = 805$$. This is correct.
Case 2: $$C=2$$. Borrow from 2. $$1 - 2$$ ends in 5, so we need to borrow from $$A$$. $$11 - 2 = 9$$, not 0. This case is invalid.
Therefore, the numbers are 922 and 117.
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