Question

one third of a tank is filled with water. when another 100 litres of water was poured in ,it became half full. howmany litres can the tank hold in all?

Answer 1

Let the tank has total capacity of x liters
When ¹/₃ is full it means to say that it has ˣ/₃ litres of water

Now when 100 litres water was added it became half full

Note:-  half full = ˣ/₂ litres and 100 litres water was added to it = ˣ/₃ +100 litres

∴ [tex] \frac{x}{2} = 100+ \frac{x}{3} [/tex]
$\frac{x}{2} - \frac{x}{3} =100$
$\frac{x}{6} = 100$
$x=600$

Therefore the tank can hold 600 litres of water...