A container when 1/2(fraction) filled with water weighs 6.5kg and when 1/4(fraction) filled weighs 4kg. Find the weight of the empty container.

Question

This is a Primary 5 question. Please respond with an understandable working and answer.

Answer 1

Let W = weight of water when ¼ FULL.  L<et c = weight of container (empty).

 

Then when half full, weight of water would be 2W, so

 

c + 2W = 6.5

c + W = 4  

 

This is Algebra; you have two equations & two unknowns.  Presumably you know how to solve ("substitution" being a key idea).

 

I will leave you to finish the job. Remember to check your solution.