The figure shows the amount of water in two rectangular tanks, H and J, at first. Ivan poured ¹₅ of the water from H into J to fill it to the top, without overflowing.

1. How much water was there in Tank H at first?
2. Ivan then poured all the water from Tank J into Tank H. 15542 cm³ of water overflowed from Tank H. What was the height of Tank H?

(a)
Volume of water to fill Tank J
= 19 x 17 x 17
= 5491 cm<sup>3

1</sup>₅ of volume of water in Tank H at first = 5491 cm^3  
5₅ of volume of water in Tank H at first = 5 x 5491 = 27455 cm³

Volume of water in Tank H at first = 27455 cm³

Volume of water in Tank J at first
= 19 x 17 x 21
= 6783 cm³

Total volume of water in Tank H and Tank J 
= 27455 + 6783
= 34238 cm³

Final volume of water in Tank H after 15542 cm³ of water overflowed
= 34238 - 15542
= 18696 cm³

Base area of Tank H
= 24 x 19
= 456 cm²

Height of Tank H
= 18696 ÷ 456 
= 41 cm

Answer(s): (a) 27455 cm² ; (b) 41 cm