cuboid empty container A is 45 cm long, 40 cm wide, and 35 cm high. A container B with a length of 40 cm, a width of 30 cm, and a water depth of 45 cm, pour part of the water in container B to A so that the water depths in the two containers are equal. How many centimeters is the water depth in container A at this time?
一个长方体空容器A，长45厘米、宽40厘米、高35厘米．一个长40厘米、宽30厘米、水深为45厘米的容器B，将容器B的水倒一部分给A，使两容器中的水深相等，这时容器A中的水深为几厘米？
<gadget id="calculator">40 * 30 * 45</gadget>
<output>54_000</output>

<gadget id="calculator">45 * 40</gadget>
<output>1_800</output>

<gadget id="calculator">40 * 30</gadget>
<output>1_200</output>

<gadget id="calculator">1_800 + 1_200</gadget>
<output>3_000</output>

<gadget id="calculator">54_000 / 3_000</gadget>
<output>18</output>

<result>18</result>