BB Recruitment test for ad 2013 What is the ration of the total sales of branch B2 for both years to the total sales of branch B4 for both years?

The bar graph given below shows the sales of books (in thousands) from six branches (B1, B2, B3, B4, B5, B6) of apublishing company during 2011 and 2012. Based on the graph answer the question.

What is the ration of the total sales of branch B2 for both years to the total sales of branch B4 for both years?