Answer:
100 g
Explanation:
Let the mass of density 1.2 g/cm³ be x gram and let the mass of density 1.8 g/cm³ be y gram
Applying
Density (D) = mass(m)/Volume (V)
Volume (V) = mass(m)/Density(D)
V = m/D........................... Equation 1
From the question,
x+y = 400...................... Equation 1
Volume of the liquidis
V = 400/1.6 = 250 cm³
(x/1.2)+(y/1.8) = 250
(1.8x/1.2)+y = 450............... Equation 1
Solving both equation simultaneously,
Subtract equation 1 from equation 2
x-(1.8x/1.2)+(y-y) = 400-450
x-1.5x = -50
-0.5x = -50
x = -50/-0.5
x = 100 g.
Hence the mass of the liquid of density 1.2 g/cm³ is 100 g
