What should be subtracted from$\frac{-5}{3}$ to get $\frac{-2}{7}$ ?

Reciprocal of a negative number is

Ram donated $\frac{1}{10}$ of his salary to an orphanage,$\frac{1}{3}$ of his salary spent on food,$\frac{1}{4}$ of salary on rent and electricity and $\frac{1}{20}$ of his salary on telephone. This month he donated $₹5000$in Prime Minister relief fund for Uttarakhand victims. He was left with $₹3000$ with him, find his monthly salary. Should we donate the money for needy people? What values are being promoted$?$

Evaluate $4\frac{2}{5}+3\frac{7}{8}$

Evaluate $7\frac{3}{4}-4\frac{3}{5}$