A rectangular tank, 70 cm by 55 cm by 45 cm, is filled with water to a height of 7 cm. The ratio of the volume of water in the tank to that in a pail is 7 : 4. If
25 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 55 x 7
= 26950 cm
3 7 u = 26950 cm
3 1 u = 26950 ÷ 7 = 3850 cm
3 4 u = 4 x 3850 = 15400 cm
3 Volume of water in
25 of the pail = 15400 cm
3 Volume of the pail
= 15400 ÷
25 = 15400 x
52 = 38500 cm
3 (b)
Volume of the tank
= 70 x 55 x 45
= 173250 cm
3 Number of pails to fill the tank
= 173250 ÷ 38500
= 4 r 19250
Minimum number of pails to fill the tank
= 4 + 1
= 5
Answer(s): (a) 38500 cm
3; (b) 5