Question

If the ratio of the area of circle A to the area of circle B is 2 : 1, then how many times larger is the circumference of circle A than the circumference of circle B? 

Answer 1

Area A / area B = 2 / 1; => radius A / radius B = $\sqrt{2}$;
circumference of circle A / circumfereance of circle B =  radius A / radius B = $\sqrt{2}$ => $\sqrt{2}$≈1.41;