A rectangular tank, 70 cm by 45 cm by 40 cm, is filled with water to a height of 9 cm. The ratio of the volume of water in the tank to that in a pail is 7 : 2. If
23 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 9
= 28350 cm
3 7 u = 28350 cm
3 1 u = 28350 ÷ 7 = 4050 cm
3 2 u = 2 x 4050 = 8100 cm
3 Volume of water in
23 of the pail = 8100 cm
3 Volume of the pail
= 8100 ÷
23 = 8100 x
32 = 12150 cm
3 (b)
Volume of the tank
= 70 x 45 x 40
= 126000 cm
3 Number of pails to fill the tank
= 126000 ÷ 12150
= 10 r 4500
Minimum number of pails to fill the tank
= 10 + 1
= 11
Answer(s): (a) 12150 cm
3; (b) 11