A book costs $₹m,$ pen costs $₹n$ more than half of the cost of book$.$ Express the total cost of a book and a pen in terms of $\text{'}m\text{'}$ and $\text{'}n\text{'}.$

It is given that cost of the book $=$$₹m$

Cost of the pen $₹n$ more than half of the cost of book

Now cost of the pen $=$$\frac{1}{2}m+n$

$=m+\frac{m}{2}+n$

Total cost of a book and a pen $=m+\frac{m}{2}+n$

Hence$,$ the total cost of pen and a book in terms of $\text{'}m\text{'}$ and $\text{'}n\text{'}$ is $\frac{3m}{2}+n$