In a given vernier callipers, n division, on the vernier scale coincide with (n–1) divisons of the main scale. The main scale has been graduated to read up to (x) units. If the zero error is (+p) times th least count, the reading when the
(i) Main scale reads (m) units
(ii) The (kth) division on the vernier scale coincides with a main scale division, is
(1) \(\left[m+\frac{x}{n}(k+p) \right]\)
(2) \(\left[m+\frac{x}{n}(k-p) \right]\)
(3) \(\left[m+(\frac{x}{n-1})(k+p) \right]\)
(4) \(\left[m+(\frac{x}{n-1})(k-p) \right]\)