Answer: The original number is 15.
Step-by-step explanation:
I think it's A becaouse the answer I got was very close to the answer of A so it's A I think. Im just tying to help c:
Answer:
We have a small circle, that is dilated by a factor of 5/3 creating a larger circle.
If the smaller circle has a diameter D, then after the dilation, the larger circle will have a diameter equal to: (5/3)*D
We know that the area of the larger circle is:
A = 100*pi cm^2.
And the area of a circle of diameter d, is:
a = pi*(d/2)^2
knowing that the diameter of the large circle is (5/3)*D, we can find the value of D.
A = pi*( (5/3)*D/2)^2 = 100*pi cm^2
let's solve this for D:
pi*( (5/3)*D/2)^2 = 100*pi cm^2
( (5/3)*D/2)^2 = 100 cm^2
( (5/3)*D/2) = √(100 cm^2) = 10cm
D/2 = (3/5)*10cm
D = 2*(3/5)*10cm = 12cm.
Then the area of the smaller circle will be:
a = pi*(D/2)^2 = pi*(12cm/2)^2 = pi*(6cm)^2 = pi*36 cm^2
and pi = 3.14
a = pi*36 cm^2 = 3.14*36cm^2 = 113.04 cm^2
Yes the person is right I was trying to type it but they beat me to it
