The fifth grade students of Lingshan Primary School were divided into three groups to go up the mountain to pick tea. Group A picked (3/4) kg, which was (1/4) kg less than group B, and group C picked (2/5) kg less than group B. How many kilograms of tea are picked in Group C?
灵山小学五年级同学分三组上山采茶，甲组采了(3/4)kg，比乙组少采(1/4)kg，丙组比乙组少采(2/5)kg．丙组采茶多少千克？
<gadget id="calculator">3 / 4</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">(1/4) - (2/5)</gadget>
<output>-3/20 = around -0.15</output>

<gadget id="calculator">(3/4) + (-3/20)</gadget>
<output>3/5 = around 0.6</output>

<result>3/5 = around 0.6</result>