Two identical buckets H and J contained some water. Bucket H was ¹₅ filled and Bucket J was ¹₆ filled. The ratio of the total mass of Bucket H and the water in it to the total mass of Bucket J and the water in it was 11 : 10. The total mass of the two buckets and the water they contained was 4620 g. What is the mass of an empty bucket?
Mass of Bucket H and the water inside = 11 u
Mass of Bucket J and the water inside = 10 u

Total mass of the two buckets and the water inside them
= 11 u + 10 u
= 21 u

21 u = 4620

1 u = 4620 ÷ 21 = 220

Mass of Bucket H and the water in it more than mass of Bucket J and the water in it 
= 11 u - 10 u
= 1 u

Fraction of the water that Bucket H had more than Bucket J 
= ¹₅ - ¹₆
= ⁶₃₀ - ⁵₃₀
= ¹₃₀ 

¹₃₀ of the water capacity → 1 u
⁵₃₀ of the water capacity → 5 x 1 u = 5 u

Mass of an empty bucket
= 10 u - 5 u
= 5 u
= 5 x 220
= 1100 g

Answer(s): 1100 g