9+4 = 13 total balls
1st pick would be 9/13 probability of picking yellow
2nd pick would be 4/13 probability
3rd pick would be 4/13 probability
total probability : 9/13 * 4/13 * 4/13 = 144/2197
Answer:
If I'm not mistaken I believe it is 100
Step-by-step explanation:
It is given that the mean is 79.1 inches and standard deviation is 3.0 inches so it follows:

So the value from 75 to 81 is given by:

Use the table or a software to get the probability values and substitute to get the probability value as:
The probability is 0.6509.