Two identical pails G and H contained some water. Pail G was ¹₃ filled and Pail H was ¹₄ filled. The ratio of the total mass of Pail G and the water in it to the total mass of Pail H and the water in it was 7 : 6. The total mass of the two pails and the water they contained was 1950 g. What is the mass of an empty pail?
Mass of Pail G and the water inside = 7 u
Mass of Pail H and the water inside = 6 u

Total mass of the two pails and the water inside them
= 7 u + 6 u
= 13 u

13 u = 1950

1 u = 1950 ÷ 13 = 150

Mass of Pail G and the water in it more than mass of Pail H and the water in it 
= 7 u - 6 u
= 1 u

Fraction of the water that Pail G had more than Pail H 
= ¹₃ - ¹₄
= ⁴₁₂ - ³₁₂
= ¹₁₂ 

¹₁₂ of the water capacity → 1 u
³₁₂ of the water capacity → 3 x 1 u = 3 u

Mass of an empty pail
= 6 u - 3 u
= 3 u
= 3 x 150
= 450 g

Answer(s): 450 g