A rectangular tank, 70 cm by 45 cm by 45 cm, is filled with water to a height of 12 cm. The ratio of the volume of water in the tank to that in a pail is 7 : 2. If
35 of the pail is filled with water, find
- the volume of the pail.
- the minimum number of such pails to fill the tank.
(a)
Volume of water in the tank
= 70 x 45 x 12
= 37800 cm
3 7 u = 37800 cm
3 1 u = 37800 ÷ 7 = 5400 cm
3 2 u = 2 x 5400 = 10800 cm
3 Volume of water in
35 of the pail = 10800 cm
3 Volume of the pail
= 10800 ÷
35 = 10800 x
53 = 18000 cm
3 (b)
Volume of the tank
= 70 x 45 x 45
= 141750 cm
3 Number of pails to fill the tank
= 141750 ÷ 18000
= 7 r 15750
Minimum number of pails to fill the tank
= 7 + 1
= 8
Answer(s): (a) 18000 cm
3; (b) 8