Dorothy

Dorothy feeds her dog during noon time with 2/5 kilograms of dog food and during night time with 3/7 kilograms of dog food. How much is dog food fed to her dog in a week?

Final Answer:

m =  5.8 kg

Step-by-step explanation:

$$\begin{gathered} a=\frac{2}{5}=0.4\text{kg} \\ b=\frac{3}{7}\doteq 0.4286\text{kg} \\ n=7 \\ d=a+b=\frac{2}{5}+\frac{3}{7}=\frac{14}{35}+\frac{15}{35}=\frac{14+15}{35}=\frac{29}{35}\doteq 0.8286\text{kg} \\ m=n\cdot d=7\cdot \frac{29}{35}=\frac{7\cdot 29}{35}=\frac{203}{35}=\frac{29}{5}\text{kg}=5.8\text{kg} \end{gathered}$$

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