Dongfeng Chemical Fertilizer Factory will produce a batch of chemical fertilizers in April. The ratio of the tonnage produced in the first week to the planned total tonnage is 1:4. If another 140 tons are produced in the second week, this batch of tasks can be completed (3 /5), how many tons of fertilizers were actually produced in the first week?
东风化肥厂四月份要生产一批化肥，第一个星期生产的吨数与计划生产总吨数的比是1：4，第二个星期如果再生产140吨，就能完成这批任务的(3/5)，第一个星期实际生产多少吨化肥？
<gadget id="calculator">3 / 5</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">1 + 4</gadget>
<output>5</output>

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

<gadget id="calculator">(3/5) - (1/5)</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">140 / (2/5)</gadget>
<output>350</output>

<gadget id="calculator">350 * (1/5)</gadget>
<output>70</output>

<result>70</result>