Ajar contains 99% fair coins, and 1% double-headed coins. you took a coin at random, then toss it 3 times and observed 3 heads. what is the probability that you picked a double-headed coin?

The probability of getting 3 heads in 3 tosses of a fair coin is:

The probability of selecting a fair coin and getting 3 heads in 3 tosses is:


The probability of selecting a double-headed coin and getting 3 heads in 3 tosses is:

The probability of selecting a coin and getting 3 heads in 3 tosses is:
0.12375 + 0.01 = 0.13375
The probability that a double-headed coin was picked is:
0.01/0.13375 = 0.0748

The answer is 0.0748 or 7.48%

Def is a scalene triangle