Combinatorial number - high school - math problems
- 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.
How many different ways can three people divide 7 pears and 5 apples?
- 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?
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
- Probability of malaria
A survey carried out at a certain hospital indicates that the probability that a patient tested positive for malaria is 0.6. What is the probability that two patients selected at random (i) one is negative while the other tested positive? (i) both patie
On the menu are 12 kinds of meal. How many ways can we choose four different meals into the daily menu?
- STRESSED word
Each letter in STRESSED is printed on identical cards, one letter per card and assembled in random order. Calculate the probability that the cards spell DESSERTS when assembled.
Of the 26 pupils in the classroom, 12 boys and 14 girls, four representatives are picked to the odds of being: a) all the girls b) three girls and one boy c) there will be at least two boys
- Three workplaces
How many ways can we divide nine workers into three workplaces if they need four workers in the first workplace, 3 in the second workplace and 2 in the third?
See also our combinations calculator.