Probability and statistics
classical probability (balls, two dice, drawing several items, drawing twice with and without replacement), complementary events, arithmetic and weighted mean, median, mode
Exercises are drawn at random from a large bank - every click gives a different set.
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Compute the weighted mean
Marks: 3, 5, 3. Their weights: 2, 2, 4.
Give the probability
A number is drawn at random from the set of all two-digit numbers. What is the probability that the number drawn is divisible by 13?
Give the probability
Two 20-sided dice are thrown. What is the probability that the numbers thrown add up to an even number?
Give the probability
Twice, with replacement, one number is drawn from the set {4, 5, 6, 7, 8, 9}. What is the probability that the sum of the numbers drawn is odd?
Give the probability
A box holds 3 white balls and 18 black balls. One ball is drawn at random. What is the probability that it is NOT white?
Compute the arithmetic mean
1, 12, 14, 3, 26
Give the median of these data
In a survey, 28 students were asked how many brothers and sisters they have in total. The results: number of siblings 0: 8 students number of siblings 1: 1 student number of siblings 2: 8 students number of siblings 3: 2 students number of siblings 4: 9 students
Give the probability
A box holds 8 white balls and 5 black balls. One ball is drawn at random. What is the probability that it is black?
Find x
The arithmetic mean of the numbers 19, 37, 26, 9, x, 31 is 21.5. What is x?
Give the probability
A box holds 4 white balls and 3 black balls. Two balls are drawn at once. What is the probability that both are white?
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