The school bought a batch of saplings, 180 trees were shipped in the first time, and 1/4 of the total number was shipped in the second time. At this time, the ratio of the trees that were shipped to the trees that were not shipped was 4:3. How many saplings does the school plan to buy?
学校买进一批树苗，第一次运来了180棵，第二次运来了总数的(1/4)，这时运来的与没运来的棵树比是4：3．学校计划买树苗多少棵？
<gadget id="calculator">3 + 4</gadget>
<output>7</output>

<gadget id="calculator">4 / 7</gadget>
<output>4/7 = around 0.571429</output>

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

<gadget id="calculator">(4/7) - (1/4)</gadget>
<output>9/28 = around 0.321429</output>

<gadget id="calculator">180 / (9/28)</gadget>
<output>560</output>

<result>560</result>