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

1. How much water was there in Tank K at first?
2. Albert then poured all the water from Tank L into Tank K. 11200 cm³ of water overflowed from Tank K. What was the height of Tank K?

(a)
Volume of water to fill Tank L
= 20 x 16 x 16
= 5120 cm<sup>3

1</sup>₅ of volume of water in Tank K at first = 5120 cm^3  
5₅ of volume of water in Tank K at first = 5 x 5120 = 25600 cm³

Volume of water in Tank K at first = 25600 cm³

Volume of water in Tank L at first
= 20 x 16 x 18
= 5760 cm³

Total volume of water in Tank K and Tank L 
= 25600 + 5760
= 31360 cm³

Final volume of water in Tank K after 11200 cm³ of water overflowed
= 31360 - 11200
= 20160 cm³

Base area of Tank K
= 24 x 20
= 480 cm²

Height of Tank K
= 20160 ÷ 480 
= 42 cm

Answer(s): (a) 25600 cm² ; (b) 42 cm