# Combinatorial number + variations - math problems

#### Number of problems found: 25

• VCP equation Solve the following equation with variations, combinations and permutations: 4 V(2,x)-3 C(2,x+ 1) - x P(2) = 0
• N-gon How many diagonals has convex 11-gon?
• Combinatorics The city has 7 fountains. Works only 6. How many options are there that can squirt ?
• Disco On the disco goes 12 boys and 15 girls. In how many ways can we select four dancing couples?
• Tournament Six teams entered the basketball tournament. How many matches will be played if each team has to play one match with each other?
• 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
• Prize How many ways can be rewarded 9 participants with the first, second and third prize in a sports competition? How many ways can we thread 4 red, 5 blue, and 6 yellow beads onto a thread?
• Combinations of sweaters I have 4 sweaters two are white, 1 red and 1 green. How many ways can this done?
• Three reds What is the probability that when choosing 3 carats from seven carats, all 3 reds will be red?
• Three-digit numbers How many three-digit numbers are from the numbers 0 2 4 6 8 (with/without repetition)?
• 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?
• Sum or product What is the probability that two dice fall will have the sum 7 or product 12?
• Sweater Dana confuses sweater and wool has a choice of seven colors. In how many ways she can choose from three colors to the sleeves?
• Sum on dice We have two dice. What is the greater likelihood of fall a total sum 7 or 8 ? (write 7, 8 or 0 if the probabilities are the same)? There are 15 boys and 12 girls at the graduation party. Determine how many four couples can be selected.
• Classroom 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
• The camp At the end of the camp a 8 friends exchanged addresses. Any friend gave remaining 7 friends his card. How many addresses they exchanged?
• Boys and girls There are eight boys and nine girls in the class. There were six children on the trip from this class. What is the probability that left a) only boys b) just two boys
• Lines How many lines can be draw with 8 points, if three points lie on one line and the other any three points do not lie on the same line?

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