Joseph's percentage error would be 1.89%
Explanation:
Exact value of the density of aluminium = 2.699 g/cm³
Calculated value of the density of aluminium = 2.75 g/cm³
Percentage error = ?
We know:
[tex]Percentage error = \frac{experimental - exact}{exact} X 100\\\\[/tex]
[tex]= \frac{2.75 - 2.699}{2.699} X 100\\\\= \frac{0.051}{2.699} X 100\\\\= 1.89\\[/tex]
Therefore, Joseph's percentage error would be 1.89%