Tank C, measuring 70 cm by 30 cm by 65 cm, was filled with water to the brim. Water was then poured from Tank C to Tank D, which has a base area of 756 cm² until the height of the water level in Tank D became thrice that of the water level in Tank C. Find the volume of water in Tank D, leaving your answer in cubic cm.
Volume of Tank C
= 70 x 30 x 65
= 136500 cm³ 

Base area of Tank C 
= 70 x 30
= 2100 cm²

Total base areas
= 2100 + 756 + 756 + 756
= 4368 cm² 

Height of the water level in Tank C after pouring
= 136500 ÷ 4368
= 31.25 cm

Height of the water level in Tank D after pouring
= 3 x 31.25 
= 93.75 cm

Volume of water in Tank D
= 756 x 93.75
= 70875 cm³ 

Answer(s): 70875 cm³