Combinatorics - math word problems - page 35 of 36
Number of problems found: 701
- Probability 7628
The probability that six will fall in just three rolls is once?
How many different circles are determined by 9 points at the plane if 6 of them lie in a straight line?
In a country 65% of people drink coffee 50% drink tea 25% drink both. What is the probability that a person chosen at random will drink neither tea nor coffee?
- Double probability
The probability of success of the planned action is 60%. What is the probability that we will achieve success at least once if this action is repeated twice?
What is the probability that a family with 7 childrens have: exactly 6 dívek? 2 dívky and 5 boys? Consider the birth probability of a girl is 48.87% and boy 51.13%.
- Alarm systems
What is the probability that at least one alarm system will signal the theft of a motor vehicle when the efficiency of the first system is 90% and of the independent second system 80%?
- Three shooters
Three shooters shoot, each one time, on the same target. The first hit the target with a probability of 0.7; second with a probability of 0.8 and a third with a probability of 0.9. What is the probability to hit the target: a) just once b) at least once c
- The university
At a certain university, 25% of students are in the business faculty. Of the students in the business faculty, 66% are males. However, only 52% of all students at the university are male. a. What is the probability that a student selected at random in the
- TV fail
The TV has average 35 failures after 10,000 hours. Find the probability of TV failure after 400 hours of operation.
- Birthday paradox
How large must the group of people be so that the probability that two people have a birthday on the same day of the year is greater than 90%?
- All use computer
It is reported that 72% of working women use computers at work. Choose 3 women at random, find the probability that all 3 women use a computer in their jobs.
From a box of spruce seeds with the germination of 80%, we randomly select 10 seeds and plant them. Find the median of the random variable: the number of germinating seeds.
- Three-digit 58943
The vortex of the three given digits formed different three-digit numbers. When she added up all these numbers, she published 1554. What numbers did Vierka use?
- Three-digit 7248
Find all three-digit numbers n with three different non-zero digits divisible by the sum of all three two-digit numbers we get when we delete one digit in the original number.
- Poisson distribution - daisies
The meadow behind FLD was divided into 100 equally large parts. Subsequently, it was found that there were no daisies in ten of these parts. Estimate the total number of daisies in the meadow. Assume that daisies are randomly distributed in the meadow.
- Intersect 5216
At how many points do ten lines intersect if no two are parallel?
- Eight blocks
Dana had the task to save the eight blocks of these rules: 1. Between two red cubes must be a different color. 2. Between two blue must be two different colors. 3. Between two green must be three different colors. 4. Between two yellow blocks must be four
- Sick days
In Canada, there are typically 261 working days per year. If there is a 4.9% chance that an employee takes a sick day. .. what is the probability an employee will use 17 OR MORE sick days in a year?
- Probability 37651
What is the probability that in a family with four children, there are: a) at least three girls b) at least one boy, if the probability of a boy is 0.51?
Records indicate 90% error-free. If 8 records are randomly selected, what is the probability that at least 2 records have no errors?
Would you like to compute count of combinations?