Question

A cup is $\frac{1}{3}$ full of milk .What part of the cup is still to be filled by milk to make it full .

Answer 1

Fraction : A fraction is used to represent the part of the whole thing .

Here, a cup is $\frac{1}{3}$ full of milk which means means $1$ part is full from $3$ part . This implies that $2$ parts are empty

So, part of the milk needed to make it full is $=\frac{2}{3}$

Hence $\frac{2}{3}$ of the cup is still to be filled by milk to make it full.