# 7th grade (12y) + multiplication principle - examples

1. No. of divisors
How many different divisors has number ??
2. Flags
How many different flags can be made from colors white, red, green, purple, orange, yellow, blue so that each flag consisted of three different colors?
3. Rectangles
How many rectangles with area 3032 cm2 whose sides is natural numbers are?
4. Coin and die
Flip a coin and then roll a six-sided die. How many possible combinations are there?
5. Seven-segmet
Lenka is amused that he punched a calculator (seven-segment display) numbers and used only digits 2 to 9. Some numbers have the property that their image in the axial or central symmetry was again give some number. Determine the maximum number of three-d
6. Logik game
Letter game Logik is a two player game, which has the following rules: 1. The first player thinks five-letter word in which no letter is not repeated. 2. The second player writes a five-letter word. 3. The first player answers two numbers - the first numbe
7. Chess
How many different ways can initiate a game of chess (first pass)?
8. Five-digit
Find all five-digit numbers that can be created from numbers 12345 so that the numbers are not repeated and then numbers with repeated digits. Give the calculation.
9. Four swords
Obelix has three helmets, four swords and five shields. How many swords must make at the blacksmith forge Metallurgix to be able to walk another 90 days in unique armor?
10. Three digits number 2
Find the number of all three-digit positive integers that can be put together from digits 1,2,3,4 and which are subject to the same time has the following conditions: on one positions is one of the numbers 1,3,4, on the place of hundreds 4 or 2.
11. Seven
Seven friends agree to send everyone a holiday card. How many postcards were sent?
12. Dd 2-digit numbers
Find all odd 2-digit natural numbers compiled from digits 1; 3; 4; 6; 8 if the digits are not repeated.
13. Pins 2
how many different possible 4 digits pins can be found on the 10-digit keypad?
14. Holidays with grandmam
We have packed three T-shirts - white, red, orange and five pants - blue, green, black, pink and yellow. How many days can we spend with the old mother if we put on a different combination of clothes every day?
15. 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?
16. How many
How many double-digit numbers greater than 30 we can create from digits 0, 1, 2, 3, 4, 5? Numbers cannot be repeated in a two-digit number.
17. Dinning room
How many different combinations can we choose if there are 3 soups, 5 kinds of main dish and 2 desserts in the dining room?
18. Glass with icecream
We have 6 kinds of ice cream and 5 kinds of fruit. We put 3 cups of ice cream and 2 fruits into each glass. How many can unique decorated glasses be?

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