There are two boxes of jujubes, A and B, and each box contains 2002 jujubes. If a number of jujubes are taken out from box B and put into box A, the number of jujubes in box A is exactly 2.5 times that of box B. How many boxes do you get?
现有甲、乙两箱红枣，每箱内装有2002个，若从乙箱拿出若干个红枣放入甲箱后，甲箱的红枣个数恰好是乙箱的2.5倍，那么，从乙箱拿到甲箱的个数是多少．
<gadget id="calculator">2_002 + 2_002</gadget>
<output>4_004</output>

<gadget id="calculator">1 + 2.5</gadget>
<output>3.5</output>

<gadget id="calculator">4_004 / 3.5</gadget>
<output>1_144</output>

<gadget id="calculator">2_002 - 1_144</gadget>
<output>858</output>

<result>858</result>