Question

Suppose you toss a fair coin repeatedly and independently. If it comes up heads, you win a dollar, and if it comes up tails, you lose a dollar. Suppose you start with $20. What is the probability you will get to $150 before you go broke?

Answer 1

it is simple as you are starting with 20 dollars so in order to make it 150 dollars you need to toss the coin 130 times .

the probability of getting heads all times = 1/130 x1/2