oic. thanks a lot. y is directly proportional to x2 x is increased by 100% find the percentage increase in y. so, y= k x2 then y= k x2 y=k 4 x2 so 4 x2 is already increased by 100%? then to find k which is y=k 4 x2 k= y/ 4 x2 find the percentage increase in y, so what i did was : y= y/4 x2 *100 x2 can somebody helpp to correct it?? thanks lotsa.