area of circle varies as the square of its radius given that area of the circle is 154 when the

Area (Circle)=pi(radius)^2
Hence for r=3.5
Putting it into formula we get
Area=22/7*(3.5^2)
38.5 sq. unit Ans
9 years agoHelpfull: Yes(0) No(0)
Area = k.R^2 (where k can be any constant value), R is a radius
154 = k * 49
k = 154/49
k =22/7
Area = (3.5*3.5*22)/ 7 = 38.5 sq. units
9 years agoHelpfull: Yes(0) No(0)
circumference pi rsquared= 22/7 x 3.5x3.5=22/7x12.25=38.5 ans=38.5
9 years agoHelpfull: Yes(0) No(0)
Let A be area of circle and r be radius of circle .
So, according to question-
A is directly proportional to r^2.
A=kr^2(k be any constant )
154= k*7*7
k=22/7
When r=3.5,
A=22/7*3.5*3.5
A=38.5 sq unit
8 years agoHelpfull: Yes(0) No(0)
38.5
154/4
8 years agoHelpfull: Yes(0) No(0)
k*r^2=154
k=154/49
so area when radius is 3.5 is= (154/49)*(7/2)*(7/2)=38.5
7 years agoHelpfull: Yes(0) No(0)

area of circle varies as the square of its radius. given that area of the circle is 154 when the radius is 7 then find the area when radius is 3.5