A coin is tossed three times. The probability of getting head and tail alternately, is

Options

A. `1//4`
B. `1//5`
C. `1//6`
D. `1//8`

Answer

A

Explanation

Total possible outcomes, `S = {HHH, HHT, HTH, THT, TTH, THH, TTT, HTT}` and desired outcomes E `= {HTH, THT}`
`rArr n(E) = 2 and n(S) = 8`
Hence, required probability `= P(E) = (n(E))/(n(S)) = 2/8 = 1/4`