Answer: Option E is the correct answer; (1 + p⁴) / (1 + p³)
Step-by-step explanation:
P (3 head) = P(first and 3 heads) + P(second coin and 3 heads)
= (1/2)×1³ + (1/2)× p³ = (1/2) × (1 + p³)
therefore P(first coin given 3 heads) = (1/2)×1³/ ((1/2)×(1 + p³))
= 1 / (1 + p³)
Also P( second coin given 3 heads) = p³ /(1 + p³)
therefore P(4th toss in heads given first 3 are heads) will be;
= P(first and 4th toss heads) + P(second and 4th toss heads)
=(1/( 1 + p³ )) × 1 + p³ / (1+p³) × p
= (1 + p⁴) / (1 + p³)
Therefore Option E is the correct answer
