How to find most likely number?
Probability that an apple picked at random from a sack is bad is 0.15.
What’s the most likely number of bad apples in a sample of 30 apples?
The answer is 4
- rotchmLv 73 months agoFavorite Answer
If you have N apples to choose from, there are then on average 0.15 * N bad ones.
With N=30 this gives 4.5 bad apples.
Since you can only have integer # of apples, then you must look at the closest possibilities (because we assume that the distribution is bell shaped). So lets look at
m = 4 and m = 5.
To have exactly m bad ones, we use:
Prob_exactly _m_bad = 30Cm * 0.15^m * (1-0.15)^(30-m).
If m = 4 what do you get?
If m = 5 what do you get?
Which is higher (meaning, more likely).
that's your answer.
- Wayne DeguManLv 73 months ago
P(bad) = 0.15
From a batch of 30 we would have 30(0.15) => 4.5
so, 4 or 5 apples