sat suite question viewer
Problem-Solving and Data Analysis
Difficulty: Medium
A box contains red pens and blue pens. If one of these pens is selected at random, what is the probability of selecting a red pen? (Express your answer as a decimal or fraction, not as a percent.)
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Explanation
The correct answer is . It's given that a box contains red pens and blue pens. If one of these pens is selected at random, the probability of selecting a red pen is the number of red pens in the box divided by the number of red and blue pens in the box. The number of red and blue pens in the box is , or . Since there are red pens in the box, it follows that the probability of selecting a red pen is . Note that 13/50 and .26 are examples of ways to enter a correct answer.