Problem 161 of 7
Use rational expressions in a rate or work context: John takes t hours to paint a fence, and Mary takes 4 hours less than John. What is their combined painting rate?.
Using a hint is okay. It just tells the trainer to give you a little more review.
Hidden until you reveal it.
combine reciprocal rates or average rates.
Hidden until you reveal it.
Model rates as amount per time and combine compatible rates.
Enter your answer
Your answer is equivalent to the expected form.
Walkthrough
Full solution stays hidden until you ask for it.
1. Identify each individual rate as work per unit time or distance per time.
2. Write rational expressions for rates.
3. Add or compare rates as the context requires.
Use the worked steps, then substitute the final answer back into the original relationship to confirm it satisfies the prompt.
Adding times directly when rates should be combined.