Question 391927
probability of getting heads = 0.8 and for getting tails = 0.2



a) probability of getting a heads, then a tails then a heads = 0.8 * 0.2 * 0.8 

= 0.128



b) probability of different cases

case 1: firstly head then tail = 0.8 * 0.2 = 0.16

case 2 :  firstly tail then head =  0.2 *0.8 = 0.16

thus, total probability of a heads and a tail = 0.16 + 0.16 = 0.32