Answer:
<em>~ 84 cm of the pop in the poster ~</em>
Step-by-step explanation:
Let us plan out our steps, and solve for each:
<em>1. Given the information, let us create a proportionality as such:</em>
7 = 1 ⇒ x - centimeters of the pop in the poster
x 12
<em>2. Now let us cross multiply, and solve through simple algebra for x:</em>
7 * 12 = x,
x =<em> 84 centimeters of the pop in the poster</em>