Mathematics - Probability Question with Solution | TestHub

A Boy whose hobby is tossing a fair coin is to score one point for every tail and two points for every head. Boy goes on tossing the coin, till his score reaches 100 or exceeds 100 . Then the probability that his score attains exactly 100 is $\frac{2}{3}+\lambda$, Number of digits in $\frac{1}{\lambda }$ is $\_\_\_\_$