The number of trees planted in Hongguang Farm last year was 50% more than the number of surviving trees in the previous year. Last year's survival rate was 80%. How much more trees were surviving last year than in the previous year?
红光农场去年植树的数量比前年成活的树木多50%，去年的成活率是80%，去年成活的树木数量比前年成活的树木数量多多少
<gadget id="calculator">50 / 100</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">80 / 100</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">(3/2) * (4/5)</gadget>
<output>6/5 = around 1.2</output>

<gadget id="calculator">(6/5) - 1</gadget>
<output>1/5 = around 0.2</output>

<result>1/5 = around 0.2</result>