Your Mom

Your Mom can clean your entire house in 3 hours. However, your dad takes 5 hours to clean the house. How long will it take for them to clean the house if they work together? (Write the numerical answer round to the nearest thousandth)

Final Answer:

x =  1.88 h

Step-by-step explanation:

$$\begin{gathered} m=3\text{h} \\ d=5\text{h} \\ x\cdot (1/m+1/d)=1 \\ x\cdot (1/3+1/5)=1 \\ 8x=15 \\ x=\frac{15}{8}=1.875 \\ x=\frac{15}{8}=1.875=\frac{15}{8}\text{h}=1.88\text{h} \end{gathered}$$

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