Bucket filled with sand has a mass of 11.15 kilograms. when it is filled with water the mass is 5.95 kilograms. the mass of the sand is twice that of the water. find the mass of the bucket in grams

Here is how you solve it
B + S = 11.15B + W = 5.95
S = 2W
          B + 2W = 11.15       -- B + 1W = 05.95                  W = 05.20
B +   W  = 5.95B + 5.20 = 5.95   -- 5.20  --5.20
B=0.75      Mass = 0.75 kilogramsHope this helps.