Question

related questions: lesson 6: common algebra word problems

q. rafael can clean a suite of offices in 60 minutes. kim can do the same job in 40 minutes, and nick can do the work in 30 minutes. if they all work together, how long will it take to do the job? (hint: figure the rate as a fraction of the job per minute.)

a. less than 13 minutes
b. between 13 and 14 minutes
c. between 14 and 15 minutes
d. greater than 15 minutes

Explanation:

Identify individual work rates

Using the Work Rate Word Problems knowledge point

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$$

Calculate combined work rate

Using the Work Rate Word Problems knowledge point

$$
LATEXBLOCK1
$$

Determine total time required

Using the Work Rate Word Problems knowledge point

$$
LATEXBLOCK2
$$

Compare with options

Using the Work Rate Word Problems knowledge point

$$ 13 < 13\frac{1}{3} < 14 $$

Answer:

• A. Less than 13 minutes
• B. Between 13 and 14 minutes (Correct answer)
• C. Between 14 and 15 minutes
• D. Greater than 15 minutes