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問題中文翻譯:
28 .The figure shows a rectangular tank of lengh 50 cm,width 30 cm and height 20 cm.(圖中展示一個長50cm闊30cm高20cm的長方形缸)
60 % of the tank is filled with water , (個缸裝有60%水)
and then stones of total volume 5700 cm cube are put into the tank .(之後有總體積5700 cm³ 的石頭放入缸裡)
If all the stones are totally submerged ,(如果石頭全部被浸入水中)
find the depth of water in the tank .(求缸中的水深)
Suggested Solution:
The volume of water before stones are put into the tank:
50 x 30 x 20 x 60% = 18000cm³
volume of content in the tank = base area(底面積) of the tank x water depth
volume of water + volume of stones = (length x width of the tank) x water depth
18000 + 5700 = (50 x 30) x water depth
water depth = 15.8

therefore, the depth of water in the tank is 15.8 cm