A mobile company that sells two models ACN-I and ACN-II of mobile, reported that·revenues from ACN-I in 2016 were down 12% from 2015 and revenue from ACN-II sales in 2016 were up by 9% from 2015. If the total revenues from sales of both the mobile models ACN-I and ACN-II in 2016 were up by 3% from 2015, what is the ratio of revenue from ACN-I sales in 2015 to revenue from ACN-II sales in 2015?

Let's assume that revenue reported from ACN-I and ACN-II sales in 2015 be X and Y respectively.

So revenue generated from ACN-I sales in 2016 = $$X(1- \frac{12}{100})$$ =$$0.88X$$

Similarly revenue generated from ACN-II sales in 2016 = $$Y(1+ \frac{9}{100})$$ =$$1.09Y$$

                   $$0.88X$$ + $$1.09Y$$ = $$(X+Y)(1+\frac{3}{100})$$

                    $$0.88X$$ + $$1.09Y$$ =     $$1.03X$$ + $$1.03Y$$

                                $$6Y = 15X$$

                                   $$\frac{X}{Y}$$ = $$\frac{2}{5}$$