Since the scaled up photo/poster has to be proportional to the original, we can come up with the equation:
[tex] \frac{4}{6} =\frac{x}{30} [/tex]
Now we can solve for x, which is the height of the scaled up poster. We cross multiply the fractions to get 6x=120. Then, we divide 6 on both sides to get x=20.
So, the height of the scaled up photo/poster must be 20 inches.
Hope this helps! Have a great day!
