To complete an embankment project, there were 180 people picking soil, which was twice the number of people digging. Later, according to the needs of the situation, the ratio of the number of people picking soil to the number of people digging was 4:5. Ask how many people should be transferred from those who pick up the soil to dig the soil?
完成一项筑堤工程，挑土的有180人，为挖土人数的2倍，后来根据情况需要，使挑土人数与挖土人数的比为4：5．问应从挑土的人中调多少人去挖土？
<gadget id="calculator">180 / 2</gadget>
<output>90</output>

<gadget id="calculator">180 + 90</gadget>
<output>270</output>

<gadget id="calculator">4 + 5</gadget>
<output>9</output>

<gadget id="calculator">4 / 9</gadget>
<output>4/9 = around 0.444444</output>

<gadget id="calculator">270 * (4/9)</gadget>
<output>120</output>

<gadget id="calculator">180 - 120</gadget>
<output>60</output>

<result>60</result>