When scaling the dimensions of a box by a factor, the surface area changes by the square of that scale factor.
Given:
- Original surface area = 120 cm²
- Scale factor = \( \frac{3}{4} \)
To find the new surface area, we calculate the square of the scale factor:
\[ \text{Scale Factor}^2 = \left(\frac{3}{4}\right)^2 = \frac{9}{16} \]
Now, we multiply the original surface area by the square of the scale factor:
\[ \text{New Surface Area} = \text{Original Surface Area} \times \text{Scale Factor}^2 \] \[ \text{New Surface Area} = 120 , \text{cm}^2 \times \frac{9}{16} \]
Calculating this:
\[ \text{New Surface Area} = 120 \times \frac{9}{16} = \frac{120 \times 9}{16} = \frac{1080}{16} = 67.5 , \text{cm}^2 \]
So, the surface area of the new box is 67.5 cm².