The mass of a box measured by a grocer’s balane is 2.3 kg. Two gold pieces of masses 20.15 g and 20.17 g are added to the box. The total mass of the box is

Here, mass of the box, m = 2.3 kgMass of one gold piece, m1 = 20.15g = 0.02015kgMass of other gold piece, m2 = 20.17g = 0.02017kg ∴Total mass = m + m1+m2= 2.3 kg+ 0.02015 kg +0.02017 kg= 2.34032 kgAs the result is correct only up to one place of decimal, therefore, on rounding off, we getTotal mass = 2.3 kg