Let the cost of a chair = Rs. $$x$$ and cost of a table = Rs. $$y$$ => $$10x + 15y = 15525$$ Multiplying the above equation by $$(frac{4}{5})$$, we get :  => $$frac{4}{5} imes (10x + 15y = 15525)$$ => $$8x + 12y = 12420$$ $$ herefore$$ Cost of 8 chairs and 12 tables is Rs. 12,420