Question of the day (May 5th) Math olympiad

Q: If the radius of a circle is increased by 100% , the area is correspondingly increased by how many percent ? pi =3.14

Method 1 :Lets say the radius of the circle is 2cm so if it is increased by 100%, it will be 4cm . thus the previous area is 12.56 and the new area is 50.24 thus if we divide this two values the answer will be 4 thus it is 400%. 

OR

Method 2: Since the formula of the area of the circle is Pi(radius)(radius) , and the pi value is constant , we just need to find the difference in values of the square of the radii . Thus it is 4 and 16 so the percentage difference is 400%