There are five fractions that differ in turn (1/25), and their ratio is: 1:3:5:7:9, then what is the sum of these five numbers.
有五个分数依次相差(1/25)，它们的比是：1：3：5：7：9，则这五个数的和是多少．
<gadget id="calculator">1 / 25</gadget>
<output>1/25 = around 0.04</output>

<gadget id="calculator">3 - 1</gadget>
<output>2</output>

<gadget id="calculator">(1/25) / 2</gadget>
<output>1/50 = around 0.02</output>

<gadget id="calculator">(1/50) * 3</gadget>
<output>3/50 = around 0.06</output>

<gadget id="calculator">(1/50) * 5</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">(1/50) * 7</gadget>
<output>7/50 = around 0.14</output>

<gadget id="calculator">(1/50) * 9</gadget>
<output>9/50 = around 0.18</output>

<gadget id="calculator">(1/50) + (3/50) + (1/10) + (7/50) + (9/50)</gadget>
<output>1/2 = around 0.5</output>

<result>1/2 = around 0.5</result>