Question

A tank weighs 5.6kg when it 1/4 filled with water.If it weighs 10.4kg when it is full ,what will be it's weight when it is empty.​

Answer 1

Answer:

4 kg

Step-by-step explanation:

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Answer 2

Answer:

4 kg

Explanation:

Let the mass of tank be 't' and water 'w'

First equation :              (when it is 1/4 filled with water)

• $\sf t + \frac{1}{4} w = 5.6$

Second equation :        (when it is filled fully with water)

• $\sf t +w = 10.4$

• $\sf w = 10.4 - t$

Insert second equation into first equation :

$\rightarrow \sf t + \dfrac{1}{4} (10.4 - t) = 5.6$

$\rightarrow \sf t - \dfrac{1}{4} t + 2.6 = 5.6$

$\rightarrow \sf \dfrac{3}{4} t = 5.6 - 2.6$

$\rightarrow \sf \dfrac{3}{4} t = 3$

$\rightarrow \sf t = 4$

The tank weights 4 kg when it is empty.