There are two rectangles with equal perimeter and different areas. The length and width of A are 80 meters and 50 meters respectively. If the length and width of the two rectangles are both increased by 10 meters, how much square meters will the area of the second rectangle be increased?
有两个周长相等而面积不等的长方形．甲的长和宽分别是80米和50米．如果两个长方形的长和宽都分别增加10米，这时乙长方形的面积增加多少平方米．
<gadget id="calculator">80 + 50</gadget>
<output>130</output>

<gadget id="calculator">10 * 130</gadget>
<output>1_300</output>

<gadget id="calculator">10 * 10</gadget>
<output>100</output>

<gadget id="calculator">1_300 + 100</gadget>
<output>1_400</output>

<result>1_400</result>