Xiaogang’s family bought a cuboid glass fish tank, 45 cm long and 30 cm wide. After Xiaogang added 20 cm of water to the water tank, he put in goldfish. When all the goldfish swam under the water, the measured water depth was 23 cm. What is the volume of the fish put in?
小刚家买了一长方体玻璃鱼缸，长45厘米，宽30厘米．小刚往水箱中加了20厘米深的水后，又放入金鱼，当金鱼全部游入水下面时，测的水深23厘米．放入的鱼的体积是多少？
<gadget id="calculator">23 - 20</gadget>
<output>3</output>

<gadget id="calculator">45 * 30 * 3</gadget>
<output>4_050</output>

<result>4_050</result>