Pump diesel liters

Three identical pumps fill 50,400 liters of diesel into the tank in 7 hours. How much more (less) diesel will they pump if we add two more pumps, and they will all work for 4 hours?

Final Answer:

Δ =  -2400 l

Step-by-step explanation:

$$\begin{gathered} V_1=50400\text{l} \\ {t}_1=7\text{h} \\ Q=\frac{V_1}{3\cdot t_1}=\frac{50400}{3\cdot 7}=2400\text{l/h} \\ {t}_2=4\text{h} \\ {V}_2=Q\cdot (2+3)\cdot t_2=2400\cdot (2+3)\cdot 4=48000\text{l} \\ \Delta =V_2-V_1=48000-50400=-2400\text{l} \end{gathered}$$

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