In a rectangle with dimensions $10 \times 10$, the new rectangle would have dimensions $11 \times 9$. The ratio of the new area to the old area is $99 / 100=(\text{B}) 99$ 
The length of a rectangle is increased by $10 \textbackslash\%$ and the width is decreased by $10 \textbackslash\%$. What percent of the old area is the new area? (2009 AMC 8, Question \#8) 

(a) $$90$$ 
(b) $$99$$ 
(c) $$100$$ 
(d) $$101$$ 
(e) $$110$$ 