Final answer:
The ratio of pairs of pants to shirts that Regina owns is 2:5. Since she has 4 pairs of pants, by setting up a proportion and cross-multiplying, it is determined that she owns 10 shirts.
Step-by-step explanation:
The student's question involves finding out the number of shirts Regina owns based on the given ratio of the number of pairs of pants to shirts she has, which is 2:5. If Regina owns 4 pairs of pants, we can set up a proportion to find the number of shirts she owns because ratios express a relationship between two quantities, maintaining the same proportion when scaled up or down.
Let's denote the number of shirts Regina owns as S. The ratio can be expressed as 2:5, which is equivalent to 4:S, since she owns 4 pairs of pants. With the provided information, we can write the proportion as follows:
2/5 = 4/S
By cross-multiplying, we get:
2 × S = 4 × 5
S = (4 × 5) / 2
S = 20 / 2
S = 10
Therefore, Regina owns 10 shirts.