The figure shows the amount of water in two rectangular tanks, J and K, at first. Zeph poured
15 of the water from J into K to fill it to the top, without overflowing.
- How much water was there in Tank J at first?
- Zeph then poured all the water from Tank K into Tank J. 2940 cm3 of water overflowed from Tank J. What was the height of Tank J?
(a)
Volume of water to fill Tank K
= 15 x 13 x 15
= 2925 cm
3
15 of volume of water in Tank J at first = 2925 cm
3
55 of volume of water in Tank J at first = 5 x 2925 = 14625 cm
3 Volume of water in Tank J at first = 14625 cm
3 Volume of water in Tank K at first
= 15 x 13 x 17
= 3315 cm
3 Total volume of water in Tank J and Tank K
= 14625 + 3315
= 17940 cm
3 Final volume of water in Tank J after 2940 cm
3 of water overflowed
= 17940 - 2940
= 15000 cm
3 Base area of Tank J
= 20 x 15
= 300 cm
2 Height of Tank J
= 15000 ÷ 300
= 50 cm
Answer(s): (a) 14625 cm
2 ; (b) 50 cm