Combinatorial number - high school - math problems
Number of problems found: 114
- Ten persons
Ten persons, each person makes a hand to each person. How many hands were given?
- Playing cards
From 32 playing cards containing 8 red cards, we choose 4 cards. What is the probability that just 2 will be red?
How many matches will be played in a football tournament in which there are two groups of 5 teams if one match is played in groups with each other and the group winners play a match for the overall winner of the tournament?
We have six wagons, two white, two blue, and two red. We assemble trains from them, wagons of the same color are exactly the same, so if we change only two white wagons on a train, it's still the same train, because I don't know any different. How many di
- Six questions test
There are six questions in the test. There are 3 answers to each - only one is correct. In order for a student to take the exam, at least four questions must be answered correctly. Alan didn't learn at all, so he circled the answers only by guessing. What
- Research in school
For particular research in high school, four pupils are to be selected from a class with 30 pupils. Calculate the number of all possible results of the select and further calculate the number of all possible results, if it depends on the order in which th
- Probability of failures
In certain productions, the probability of failures is 0.01. Calculate the probability that there will be more than 1 failure among the 100 selected products if we return the selected products to the file after the check.
- 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.
- Table and chairs
Four people should sit at a table in front of a row of 7 chairs. What is the probability that there will be no empty chair between them if people choose their place completely at random?
How many different ways can three people divide 7 pears and 5 apples?
In the shop sell 4 kinds of fruits. How many ways can we buy three pieces of fruit?
In the flower shop they sell roses, tulips and daffodils. How many different bouquets of 5 flowers can we made?
- Twelve flowers
A florist has roses, tulips, daffodils, and carnations to use in flower arrangements. If she were to make an arrangement using 12 flowers, how many different combinations of these 4 types of flowers would be possible?
- Pairs of socks
Ferdinand has twelve pairs of socks, one sock is leaky. What is the probability of putting on a leaky sock?
How many ways can we thread 4 red, 5 blue, and 6 yellow beads onto a thread?
- Cube construction
A 2×2×2 cube is to be constructed using 4 white and 4 black unit cube. How many different cubes can be constructed in this way? ( Two cubes are not different if one can be obtained by rotating the other. )
- Two groups
The group of 10 girls should be divided into two groups with at least 4 girls in each group. How many ways can this be done?
- Graduation party
There are 15 boys and 12 girls at the graduation party. Determine how many four couples can be selected.
Records indicate 90% error-free. If 8 records are randomly selected, what is the probability that at least 2 records have no errors?
- Genetic disease
One genetic disease was tested positive in both parents of one family. It has been known that any child in this family has a 25% risk of inheriting the disease. A family has 3 children. What is the probability of this family having one child who inherited
See also our combinations calculator.