The line graph shows the production (in tonnes) and the sales (in tonnes) of a company.

What is the ratio of the production of the company in 2015 and 2016 taken together to the sales in 2017 and 2019 taken together? 

307 : 254

Production of the company in 2015 and 2016  :   Sales in 2017 and 2019

 ( 600 + 628 )  :   ( 500 + 516 )

        1228       :         1016

         307        :          254