Answer:
The answer is option (D). 4+b=16;b=12 more books
Step-by-step explanation:
Step 1: Derive expression for total number of books to be read
The expression for the total number of books to be read is;
T=a+b.... equation 1
where;
T=total number of books to be read
a=total number of books already read
b=number of books not read
In our case;
T=16 books
a=4 books
b=unknown
replacing;
16=4+b
4+b=16...equation 2
solving;
b=16-4
b=12
You need to read 12 more books to reach your target
