Barrel keg filling

Behind the house stands a barrel with 0.25 hectoliters of water. The father gradually takes 12 liters of fragile water from it for watering until the last 10 liters of water remain at the bottom. At most, how many full kegs could the father fill from this barrel?

Final Answer:

n =  1

Step-by-step explanation:

$$\begin{gathered} V=0.25\text{hl}\to \text{l}=0.25\cdot 100\text{l}=25\text{l} \\ {V}_1=12\text{l} \\ {V}_2=10\text{l} \\ {n}_1=(V-V_2)/V_1=(25-10)/12=\frac{5}{4}=1\frac{1}{4}=1.25 \\ n=\lfloor n_1\rfloor =\lfloor 1.25\rfloor =1 \end{gathered}$$

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