Question

下列表达式

$\dfrac{1}{10} + \dfrac{2}{20} + \dfrac{3}{30}$

的值是

The value of

$\dfrac{1}{10} + \dfrac{2}{20} + \dfrac{3}{30}$

is

$0.1$

$0.123$

$0.2$

$0.3$

$0.6$

知识点：分数

每个分数都能约分成同一个值

Each fraction reduces to the same value

$\dfrac{2}{20} = \dfrac{1}{10}$ ，且 $\dfrac{3}{30} = \dfrac{1}{10}$ 。

$\dfrac{2}{20} = \dfrac{1}{10}$ and $\dfrac{3}{30} = \dfrac{1}{10}$

每个分数都等于 $\dfrac{1}{10} = 0.1$ ，因为 $\dfrac{2}{20} = \dfrac{3}{30} = \dfrac{1}{10}$ 。

所以和是 $0.1 + 0.1 + 0.1 = 0.3$ 。

所以正确答案是 D。

Each fraction equals $\dfrac{1}{10} = 0.1,$ since $\dfrac{2}{20} = \dfrac{3}{30} = \dfrac{1}{10}.$

So the sum is $0.1 + 0.1 + 0.1 = 0.3.$

Thus, the correct answer is D .