# 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?

**Result****Leave us a comment of example and its solution (i.e. if it is still somewhat unclear...):**

**Showing 0 comments:**

**Be the first to comment!**

#### To solve this example are needed these knowledge from mathematics:

## Next similar examples:

- Disco

On the disco goes 12 boys and 15 girls. In how many ways can we select four dancing couples? - Trinity

How many different triads can be selected from the group 38 students? - Tricolors

From the colors - red, blue, green, black and white, create all possible tricolors. - Class pairs

In a class of 34 students, including 14 boys and 20 girls. How many couples (heterosexual, boy-girl) we can create? By what formula? - Fish tank

A fish tank at a pet store has 8 zebra fish. In how many different ways can George choose 2 zebra fish to buy? - Examination

The class is 21 students. How many ways can choose two to examination? - Medals

In how many ways can be divided gold, silver and bronze medal among 21 contestant? - Olympics metals

In how many ways can be win six athletes medal positions in the Olympics? Metal color matters. - Hockey

Hockey match ended 8:2. How many different matches could be? - Volleyball

8 girls wants to play volleyball against boys. On the field at one time can be six players per team. How many initial teams of this girls may trainer to choose? - Combinatorics

The city has 7 fountains. Works only 6. How many options are there that can squirt ? - First class

The shipment contains 40 items. 36 are first grade, 4 are defective. How many ways can select 5 items, so that it is no more than one defective? - Confectionery

The village markets have 5 kinds of sweets, one weighs 31 grams. How many different ways a customer can buy 1.519 kg sweets. - Metals

In the Hockey World Cup play eight teams, determine how many ways can they win gold, silver and bronze medals. - Division

Division has 18 members: 10 girls and 6 boys, 2 leaders. How many different patrols can be created, if one patrol is 2 boys, 3 girls and 1 leader? - Cars plates

How many different licence plates can country have, given that they use 3 letters followed by 3 digits? - Task of the year

Determine the number of integers from 1 to 10^{6}with ending four digits 2006.