A dilated figure has a surface area of 10,990.8 in.^2. The figure was dilated by a scale factor of 6. What is the surface area of the original figure?

a. 395,688.8 in.^2
b. 915.9 in.^2
c. 305.3 in.^2
d. 1,831.8 in.^2

1 answer

When a figure is dilated by a scale factor \( k \), the surface area of the dilated figure is related to the original surface area \( A \) by the formula:

\[ \text{Surface Area of Dilated Figure} = k^2 \times \text{Surface Area of Original Figure} \]

In this case, the scale factor \( k \) is 6, and the surface area of the dilated figure is 10,990.8 in². We can set up the equation as follows:

\[ 10,990.8 = 6^2 \times \text{Surface Area of Original Figure} \]

Calculating \( 6^2 \):

\[ 6^2 = 36 \]

Now we can rewrite the equation:

\[ 10,990.8 = 36 \times \text{Surface Area of Original Figure} \]

Now, we solve for the Surface Area of the Original Figure:

\[ \text{Surface Area of Original Figure} = \frac{10,990.8}{36} \]

Calculating that gives:

\[ \text{Surface Area of Original Figure} = 305.3 \text{ in}^2 \]

Therefore, the surface area of the original figure is \( 305.3 \text{ in}^2 \), which corresponds to option:

c. 305.3 in²