There are 180 people in two groups, A and B. The number of people in group A (1/4) is equal to the number of people in group B (1/5). How many people are there in group A? what is the correct form
甲、乙两组共有180人，甲组人数的(1/4)和乙组人数的(1/5)相等，问甲组有多少人？正确形式是多少
<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

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

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

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

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

<gadget id="calculator">1 / (4/5)</gadget>
<output>5/4 = around 1.25</output>

<gadget id="calculator">1 + (5/4)</gadget>
<output>9/4 = around 2.25</output>

<gadget id="calculator">180 / (9/4)</gadget>
<output>80</output>

<result>80</result>