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解答

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2 - \frac{1}{4}

\frac{7}{4}

十进制

1.75

求解步骤

2 - \frac{1}{4}

将项转换为分式:

2 = \frac{2 \cdot 4}{4}

= \frac{2 \cdot 4}{4} - \frac{1}{4}

因为分母相等，所以合并分式:

\frac{a}{c} \pm \frac{b}{c} = \frac{a \pm b}{c}

= \frac{2 \cdot 4 - 1}{4}

2 \cdot 4 - 1 = 7

= \frac{7}{4}

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