Two identical buckets B and C contained some water. Bucket B was ¹₂ filled and Bucket C was ¹₃ filled. The ratio of the total mass of Bucket B and the water in it to the total mass of Bucket C and the water in it was 6 : 5. The total mass of the two buckets and the water they contained was 1760 g. What is the mass of an empty bucket?
Mass of Bucket B and the water inside = 6 u
Mass of Bucket C and the water inside = 5 u

Total mass of the two buckets and the water inside them
= 6 u + 5 u
= 11 u

11 u = 1760

1 u = 1760 ÷ 11 = 160

Mass of Bucket B and the water in it more than mass of Bucket C and the water in it 
= 6 u - 5 u
= 1 u

Fraction of the water that Bucket B had more than Bucket C 
= ¹₂ - ¹₃
= ³₆ - ²₆
= ¹₆ 

¹₆ of the water capacity → 1 u
²₆ of the water capacity → 2 x 1 u = 2 u

Mass of an empty bucket
= 5 u - 2 u
= 3 u
= 3 x 160
= 480 g

Answer(s): 480 g