The figure shows the amount of water in two rectangular tanks, H and J, at first. David poured
15 of the water from H into J to fill it to the top, without overflowing.
- How much water was there in Tank H at first?
- David then poured all the water from Tank J into Tank H. 16080 cm3 of water overflowed from Tank H. What was the height of Tank H?
(a)
Volume of water to fill Tank J
= 20 x 18 x 17
= 6120 cm
3
15 of volume of water in Tank H at first = 6120 cm
3
55 of volume of water in Tank H at first = 5 x 6120 = 30600 cm
3 Volume of water in Tank H at first = 30600 cm
3 Volume of water in Tank J at first
= 20 x 18 x 21
= 7560 cm
3 Total volume of water in Tank H and Tank J
= 30600 + 7560
= 38160 cm
3 Final volume of water in Tank H after 16080 cm
3 of water overflowed
= 38160 - 16080
= 22080 cm
3 Base area of Tank H
= 24 x 20
= 480 cm
2 Height of Tank H
= 22080 ÷ 480
= 46 cm
Answer(s): (a) 30600 cm
2 ; (b) 46 cm