Geoff has a bag that contains 4 red marbles and 6 blue marbles. He chooses two marbles at random and does not replace them. What
1 answer:
Total number of marbles = 10
Number of red marbles = 4
Number of blue marbles = 6
Probability =
The probability that the first marble is blue =
The probability that the first marble is red = ; 9 because 1 marble has already been taken out.
Joint probability= probability of event A * Probability of event B
= =
You might be interested in
Answer:
The middle 92% of all heights fall between 64.4 inches and 74.2 inches.
Step-by-step explanation:
Problems of normally distributed samples are solved using the z-score formula.
In a set with mean and standard deviation
, the zscore of a measure X is given by:
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
In this problem, we have that:
Between what two values does that middle 92% of all heights fall?
The middle 92% falls from X when Z has a pvalue of 0.5 - 0.92/2 = 0.04 to X when Z has a pvalue of 0.5 + 0.92/2 = 0.96. So from the 4th percentile to the 96th percentile.
4th percentile
X when
96th percentile
X when
The middle 92% of all heights fall between 64.4 inches and 74.2 inches.