The number of electrons present in the valance shell of central atom of methyl carbocation is:
Atomic no. of C is 6(1s2,2s2,2p2). Methyl carbocation contains 3 bond. So it has 6 electron in last orbit and it has already 2 electron in 1s2 which is not involved in bonding. Hence total 8 electron or 4 pairs of electrons.