Sets + reason - math problems

Number of problems found: 52

• Left handed
It is known that 25% of the population is left-handed. What is the probability that there is a maximum of three left-handers at a seminar where there are 30 participants?
• Mba studium
At MBA school, fourth-year students can choose from three optional subjects: a) mathematical methods, b) social interaction, c) management Each student studies one of these subjects. The mathematical methods studied 28 students, the social interaction 27
• Utopia Island
The probability of disease A on the island of Utopia is 40%. The probability of occurrence among the men of this island, which make up 60% of all the population (the rest are women), is 50%. What is the probability of occurrence of A disease among women o
• Three students
Three students independently try to solve the problem. The first student will solve a similar problem with a probability of 0.6, the second student will solve at a probability of 0.55, and the third will solve at a probability of 0.04. The problem is reso
• Triangles
Ivo wants to draw all the triangles whose two sides of which have a length of 4 cm and 9 cm, and the length of the third side is expressed in whole centimeters. How many triangles does he have?
• Subsets
How many 19 element's subsets can be made from the 26 element set?
• Gloves
Petra has ten pairs of gloves in the closet. Six pairs are blue, 4 pairs are yellow. How many pieces of gloves need to be pulled out, at least when she pulls them out in the dark and wants to have one complete one-color pair?
• Italian writer
There were 17 children in the barracks with an Italian writer. 6 children ordered a book in an Italian original and 12 children in the translation. How many children ordered a book in both languages if the three children did not order it?
• Math logic
There are 20 children in the group, each two children have a different name. Alena and John are among them. How many ways can we choose 8 children to be among the selected A) was John B) was John and Alena C) at least one was Alena, John D) maximum one wa
• Rings - intersect
There are 15 pupils on the sporting ring. 10 pupils go to football, 8 pupils go to floorball. How many pupils go to both rings at the same time?
There were a total of 200 cookies in the box. They used sugar and chocolate icing in their production. They used chocolate icing for 157 biscuits. They used sugar icing for 100 biscuits. How many of these cookies have both toppings?
• Skoda cars
There were 16 passenger cars in the parking. It was the ten blue and 10 Skoda cars. How many blue Skoda cars are in the parking?
• Toy store
In the toy department of store was exposed 28 dolls. 19 dolls were blondes or could speak. 12 dolls were blondes, 14 could speak. How many blondes could speak in the toy department? How many blondes could not speak?
• Rings groups
27 pupils attend some group; dance group attends 14 pupils, 21 pupils sporty group and dramatic group 16 pupils. Dance and sporting attend 9 pupils, dance and drama 6 pupil, sporty and dramatic 11 pupils. How many pupils attend all three groups?
• Billiard balls
A layer of ivory billiard balls of radius 6.35 cm is in the form of a square. The balls are arranged so that each ball is tangent to every one adjacent to it. In the spaces between sets of 4 adjacent balls other balls rest, equal in size to the original.
• Summer camp
Out of the 180 students at a summer camp, 72 signed up for canoeing. Twenty-three students signed up for trekking, and 13 of those students also signed up for canoeing. Use a two-way table to organize the information and answer the following question: App
• Dices throws
What is the probability that the two throws of the dice: a) Six falls even once b) Six will fall at least once
• Chamber
In the chamber light is broken and all from it must be taken at random. Socks have four different colors. If you want to be sure of pulling at least two white socks, we have to bring them out 28 from the chamber. In order to have such certainty for the pa
• Czech crowns
Small Petra save money. Grandfather give her 10 crowns. Petra asked his older sister let her calculate how much he has saved up. Sister told her that he has less than 30 crowns. If the sum is divided by three left one crown. If the sum is divided by the f