Question

Now we are given the data of number of books sold by a bookstore during 5 consecutive years.

$\begin{align}
  & \text{a) about how many books were sold in 1989, 1990, 1992?} \\
 & \text{b) In which year about 475 books were sold and in chich year about 225 books were sold}\text{. } \\
\end{align}$

Answer 1

Hint:Now to read a bar graph first consider any bar representing the year. Now check the height of the bar graph with the vertical axis given. Hence we will get a number corresponding to each bar. In our case since the vertical axis represents the number of books sold by a bookstore, we will get the number of books sold each year. Hence we can check and answer the required question.

Complete step by step answer:
Now first let us consider the given bar graph.

Now in the graphlet, us check the bar representing the year 1989.
We can see that the height of the bar is 175.
Hence we can say that the number of books sold in 1989 is 175.
Now consider the bar representing the year 1990
Now we can see that the height of the bar is 475.
Hence we can say that 475 books were sold in the year 1990.
Now similarly let us consider the year 1992.
We can see that the height of the bar representing the year 1992 is 225.
Hence we can say that 225 books were sold in the year 1992.
Now to check in which year 475 books were sold just check each year to see which bar has height 475. By this, we can see that in the year 1990, 475 books were sold.
In a similar manner, we will check which bar has a height of 225.
We can see that the bar representing the year 1992 has a height of 225.
Hence in the year 1992, 225 books were sold.

Note:
Note that while checking the bar graph we might not always get the exact value of height because the scale is larger. For example, if the vertical scale is 100 we cannot see 25. In such cases, we can still calculate an approximate height. For example, if we see that the height of the bar is exactly between 100 and 200 then the height is 150. Similarly if it is $\dfrac{3}{4}$ above 100 then we can say that the height is $100+\dfrac{3}{4}\times 100=100+75=175$ .