The figure shows the amount of water in two rectangular tanks, L and M, at first. Elijah poured
15 of the water from L into M to fill it to the top, without overflowing.
- How much water was there in Tank L at first?
- Elijah then poured all the water from Tank M into Tank L. 15120 cm3 of water overflowed from Tank L. What was the height of Tank L?
(a)
Volume of water to fill Tank M
= 20 x 17 x 17
= 5780 cm
3
15 of volume of water in Tank L at first = 5780 cm
3
55 of volume of water in Tank L at first = 5 x 5780 = 28900 cm
3 Volume of water in Tank L at first = 28900 cm
3 Volume of water in Tank M at first
= 20 x 17 x 19
= 6460 cm
3 Total volume of water in Tank L and Tank M
= 28900 + 6460
= 35360 cm
3 Final volume of water in Tank L after 15120 cm
3 of water overflowed
= 35360 - 15120
= 20240 cm
3 Base area of Tank L
= 22 x 20
= 440 cm
2 Height of Tank L
= 20240 ÷ 440
= 46 cm
Answer(s): (a) 28900 cm
2 ; (b) 46 cm