Question

A fish tank has length \[40\] cm, breadth \[60\] cm and height \[50\] cm. It contains \[50\] litres of water. How many litres more water will be needed to completely fill the tank?

Answer 1

Hint: To find the capacity of the fish tank, at first, we have to find out its volume. We will get the volume in the cube cm unit. We will convert that into litre. Finally we can find the answer.

Complete step-by-step answer:
It is given that the length, breadth and height of the fish tank is \[40\] cm, \[60\] cm and \[50\] cm respectively. Also, it is given that it contains \[50\] litres of water.
We know that, \[1000\] cube cm \[ = 1\] litre
To find the capacity of the fish tank, at first, we have to find out its volume.
We know that, if \[l,b,h\] be the length, breadth and height of a cuboid, then its volume is \[l \times b \times h\] cube cm.
Substitute the values of length, breadth and height we get,
The volume of the fish tank is \[40 \times 60 \times 50\]cube cm
Let us simplify the volume of the fish tank we get,
The volume of the tank is \[120000\] cube cm.
The capacity of the tank in litres is found by dividing the cubic centimetre by 1000
So, the capacity of the tank is \[\dfrac{{120000}}{{1000}}\] litres\[ = 120\] litres
Now, we know that the tank has \[50\] litres of water.
To fill the tank, it needs more water.
So, the required amount of water is \[120 - 50 = 70\] litre of water.
Hence, \[70\] litres more water will be needed to completely fill the tank.

Note: We know that, if \[l,b,h\] be the length, breadth and height of a cuboid, then its volume is \[l \times b \times h\] cube cm.
While converting cubic centimetre to litres we should be careful as we have to divide the value which is in cubic centimetre by 1000.
To convert litres to cubic centimetre we should multiply the litre value by 1000.