Variations + natural numbers - practice problems
Number of problems found: 43
- Three dices
What is the probability that the sum of points 14 will be a roll of three dice (B, M, Z)?
- Covid-19 spread
A Street has 13 houses in a row. Some resident sin the first house tested positive for Covid-19. The virus spreads in 2 ways: It can spread to the next house or jump directly to the third house. Residents of house 2 can get infected in only one way, house
- Five number code
I have a 5 digit code on the bag that I forgot. All I remember is that it was a symmetric number and the sum of its digits was 22. Write all the numbers that can be a code. .
- Hockey Championships
At the 2021 World Hockey Championships, there are eight teams in Group A, each of which plays seven matches. There are 4 points for each team to gain points (3-2-1-0), but it is always paired with the opponent's points ( 0-1-2-3). How many points are ther
- How many 13
How many ways can X³ y⁴ z³ be written without an exponent?
- There 8
There are 7 women and 5 men in a department. a) how many ways can a committee of 3 people be selected? b) how many ways can a committee of 2 men and 1 woman be selected? c) how many ways can a committee of at least 2 woman be selected (3 people total)?
- Three wagons
I have 6 different people (A, B, C, D, E, F), which I have to place into 3 wagons, if it depends on who will board. How many options are there?
In how many ways could 9 participants of the school round of five-in-a-row win the first three places?
- Permutations with repetitions
How many times the input of 188.8.131.52.3.3.4 can be permutated into 4 digits, 3 digits and 2 digits without repetition? Ex: 4 digits = 1223, 2213, 3122, 2313, 4321. . etc 3 digits = 184.108.40.2062. . etc 2 digits = 12, 21, 31, 23 I have tried permutation fo
- Cups on the shelf
Two green, three red, and two yellow cups should be placed side by side on the shelf. a) How many different ways of setting up can arise? b) How many different ways of arranging can arise if cups of the same color stand side by side?
The father wants to plant 2 seedbeds of carrot and 2 seedbeds of onion. Use a tree chart to find how many different options for placing the seedbeds he has.
- Number 4
Kamila wrote all natural numbers from 1 to 400 inclusive. How many times did she write the number 4?
- Wedding guests
Fifteen wedding guests could not agree on who would stand in the wedding photo. The groom suggested that all possible sets of wedding guests be made in the photographs.
- Big numbers
How many natural numbers less than 10 to the sixth can be written in numbers: a) 9.8.7 b) 9.8.0
- You have
You have 4 reindeer and you want to have 3 fly your sleigh. You always have your reindeer fly in a single-file line. How many different ways can you arrange your reindeer?
- How many 4
How many four-digit numbers that are divisible by ten can be created from the numbers 3, 5, 7, 8, 9, 0 such no digits repeats?
- Coffe cups
We have 4 cups with 4 different patterns. How many possible combinations can we create from 4 cups?
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
- 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
- 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. )
See also our variations calculator. Variations - practice problems. Natural numbers - practice problems.