Let the weight of vesel = x kg Then, 1/4 of volume of water = (5.25 - x)kg Full volume of water = (16.5 - x)∴ 4(5.25 - x) = (16.5 - x)⇒ 21 - 4x = 16.5 - x ⇒ 21 - 16.5 = 3x ∴ x = 4.5/3 = 1.5 kg
Given Expression = (.53)³ - (.42)³- 3 x .58 x .42 x (.58-.42)= a³-b³ -3ab(a - b) = (a - b)³(where a = .58 and b=.42)= (.58 - .42 )³ = .16 x .16 x .16 = 0.004096