Question

The mass of a box measured by a grocer’s balance is $2.300kg$. Two gold pieces of masses $20.15g\text{and}20.17g$ are added to the box. What is
i) The Total mass of the box.
ii) The difference in the masses of the pieces to correct significant figures.

Answer 1

i) Given:
mass of the box, $m_1=2.300kg$
mass of the gold piece $I,m_2=20.15g$
mass of the gold piece $II,m_3=20.17g$
Total mass of the box $=m_1+m_2+m_3$
$=(2.3+0.02015+0.02017)$
$=2.3kg$

ii) Given:
mass of the box, $m_1=2.300kg$
mass of the gold piece $I,m_2=20.15g$
mass of the gold piece $II,m_3=20.17g$
The difference in masses = $m_2-m_1$
$=20.17-20.15$
$=0.02g$