# Changes

'''To prove'''': Consider the map $\varphi: G/K \to G/H$. Choose $g \in G$ and consider the left coset $gH$. Then, the subset of $G/K$ comprising left cosets contained in $gH$ (i.e., left cosets that map to $gH$ under $\varphi$ ) can be put in bijection with $H/K$.
'''Proof''': We explicitly construct such a bijection $\psi$ based on the choice of $g$, defined as: