Final answer:
By cancelling out the units of pens and simply multiplying the numbers, the calculation gives us 5.25 tongue depressors.
Step-by-step explanation:
To perform the calculation of 3.5 paper clips × 1 pen ÷ 1 pen × 1.5 tongue depressors, we first analyze the units involved. We can disregard the pens since they appear in both the numerator and the denominator and will cancel each other out. This simplifies the calculation to just 3.5 paper clips × 1.5 tongue depressors.
When we multiply 3.5 by Since the units of paper clips are not relevant in this context, our final answer is simply in the unit of tongue depressors.
Therefore, the correct answer is 5.25 tongue depressors.