Answer:
0.001709
Step-by-step explanation:
The probability of getting 9 tails then 1 head is:
(½)⁹ (½)¹ = (½)¹⁰
The probability of getting 10 tails then 1 head is:
(½)¹⁰ (½)¹ = (½)¹¹
The probability of getting 11 tails then 1 head is:
(½)¹¹ (½)¹ = (½)¹²
The total probability is:
(½)¹⁰ + (½)¹¹ + (½)¹²
0.001709
