Posted by Anonymous on .
The surface area of a piece of gold is directly proportional to the square of its weight. By what ratio should the weight be adjusted so as to double the surface area.

Mathematics 
bobpursley,
surface area= k w^2
w=sqrt (area/k)
double surface area.
w'=w sqrt2 
Mathematics 
Anonymous,
Thanks.I had a similar question in my recent exam. I followed a similar procedure...Made a silly error though at the end,forgot to square root..I ended up with w^2'=2w^2.