Rule for determination of total number of hybrid orbitals if sum of no. of valence electron is less than 8?

if sum of no. of e^- is less than 8 .you should divide the no. of e^- by 2 and cfind the quotiant.

if quotiant is-

2   -    sp hybridisation

3   -    sp² hybridisation

4   -    sp³ hybridisation