Variations - practice for 14 year olds - page 7 of 9
Number of problems found: 164
- White and black balls
There are seven white and three black balls in an opaque pocket. The balls are the same size. a) Randomly pull out one ball. What is the probability that it will be white? We pull out one ball, see its color, and return it to the pocket. Then we pull out - Themselves 3463
How many different ways can members of a 7-member philatelic circle elect a secretary and a steward from among themselves? - Attempts 3460
How many attempts do I need to guess the 3-digit PIN to be sure I can guess it? - Two-digit 3456
Write all the two-digit numbers that can be composed of the digit 7,8,9 without repeating the digits. Which ones are divisible b) two, c) three d) six?
- Metals
In the Hockey World Cup, play eight teams, and determine how many ways they can win gold, silver, and bronze medals. - Prize
How many ways can 9 participants be rewarded with the first, second, and third prizes in a sports competition? - Olympics metals
How many ways can one win six athletes' medal positions in the Olympics? Metal color matters. - Combinations of sweaters
I have four sweaters, two are white, one red and one green. How many ways can you sort it out? - 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
- Eight blocks
Dana had the task of saving the eight blocks of these rules: 1. Between two red cubes must be a different color. 2. Between two blue must be two different colors. 3. Between two green must be three different colors. 4. Between two yellow blocks must be fo - Keyboards keys
Michael had small keys on the shelf, which you can see in the picture. Their tones were marked on the white keys. Little Clara found the keys. As she took them off the shelf, they fell out of her hand, and all the white keys spilled out. So that the broth - Pupils
Four pupils are going via the dark hall. Start at one side and have to get to the other side for 17 minutes. They have only one lamp for the trip. The corridor is narrow. They can go up two pupils at a time and at a slower speed. Each pupil went different - Password dalibor
Kamila wants to change the password daliborZ by a) two consonants exchanged between themselves, b) changes one little vowel to such same great vowel c) makes these two changes. How many opportunities do you have a choice? - Football league
In the football league is 16 teams. How many different sequences of results may occur at the end of the competition?
- Three-digit numbers
How many three-digit numbers are from the numbers 0 2 4 6 8 (with/without repetition)? - Neighborhood
I have 7 cups: 1 2 3 4 5 6 7. How many opportunities for standings cups are there if 1 and 2 are always neighborhood? - Olympics
How many ways can six athletes be placed on the podium at the Olympics? Depend on the color of the metal. - Three-digit
How many three-digit natural numbers are greater than 321 if no digit in the number is repeated? - Friends in cinema
5 friends went to the cinema. How many possible ways can they sit in a row if one of them wants to sit in the middle and the remaining place does not matter?
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