Doubt from solutions

we can use same concept of dilution formula type because for liquids molarity=molality some case or just think
\frac{m_1}{m_2}= \frac{5}{2} hence extra molarity will ration tends out to be \frac{3}{2}
jee main problm 2018 or 17??

@Sneha_2021 2019 11th Jan 1st shift