Powder washes

Mrs. Jane bought washing powder that weighed 5 kg. The powder is enough for 50 washes. However, she decided to fill the measuring cup with powder only three-fifths of the volume. How many washes does the powder last for her?

Final Answer:

n =  83

Step-by-step explanation:

$$\begin{gathered} m=5\text{kg} \\ {m}_1=m/50=5/50=\frac{1}{10}=0.1\text{kg} \\ {m}_2=3/5\cdot m_1=3/5\cdot 0.1=\frac{3}{50}=0.06\text{kg} \\ {n}_1=m/m_2=5/0.06=\frac{250}{3}=83\frac{1}{3}\doteq 83.3333 \\ n=\lfloor 50\cdot 5/3\rfloor =83 \end{gathered}$$

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