A retail company has hired 10 new employees and wants to send them to work in its stores. In how many ways can this be done (a) if the company has 2 stores?

(b) if the company has 2 stores and wants to send 5 new employees to each of them?

(c) if the company has one main store, where it wants to send 6 new employees, and 2 local stores, to each of which it wants to send 2 new employees?

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31  7                43      3                78    10                  917    4

_=3-                      _=4  _                  _=  4 _                      _=83_

8        8                10      10            17        17                  11        11

выглядет это примерно так:

1000001

1000010

1000100

1001000

1010000

1100000

таких чисел будет шесть!

x - количество книг на полке изначально

3(x-18)=x+18

3x-54=x+18

3x-x=54+18

2x=72

x=36

ответ: 36 книг