Final answer:
The similarity ratio of two trapezoids with areas of 49 cm² and 9 cm² is found by taking the square root of the ratio of their areas, resulting in a similarity ratio of 7:3, which is option A.
Step-by-step explanation:
The question involves understanding the concept of similarity ratio, particularly as it applies to two-dimensional figures like trapezoids. To find the similarity ratio of two similar trapezoids with different areas, we can compare the areas directly. The ratio of the areas of two similar figures is the square of the scale factor (similarity ratio).
For two similar trapezoids with areas of 49 cm² and 9 cm², we take the square root of the ratio of their areas to find the linear similarity ratio:
Similarity Ratio = √(Area of larger trapezoid / Area of smaller trapezoid) = √(49/9) = √(49)/√(9) = 7/3.
Therefore, the similarity ratio of the two trapezoids is 7:3, which corresponds to option A.