13) $\frac{- (- 1)}{21} - \frac{1}{28}$

Question

13) $\frac{- (- 1)}{21} - \frac{1}{28} = \frac{1}{21} - \frac{1}{28} = \frac{4}{84} - \frac{3}{84} = \frac{1}{84}$

Answer 1

Trả lời:

Giải bởi Vietjack

13) $\frac{- (- 1)}{21} - \frac{1}{28} = \frac{1}{21} - \frac{1}{28} = \frac{4}{84} - \frac{3}{84} = \frac{1}{84}$

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