In a square, one side is extended by (1/2) and the other side is extended by (1/5) to obtain a rectangle. How much does the area of the rectangle increase compared to the square?
一个正方形，一条边长延长(1/2)，另一条边长延长(1/5)后到得一个长方形，长方形面积比正方形增加了多少
<gadget id="calculator">1 * 1</gadget>
<output>1</output>

<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">1 * (1/2)</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">1 + (1/2)</gadget>
<output>3/2 = around 1.5</output>

<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 * (1/5)</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 + (1/5)</gadget>
<output>6/5 = around 1.2</output>

<gadget id="calculator">(3/2) * (6/5)</gadget>
<output>9/5 = around 1.8</output>

<gadget id="calculator">(9/5) - 1</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">(4/5) / 1</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">(4/5) * 1</gadget>
<output>4/5 = around 0.8</output>

<result>4/5 = around 0.8</result>