Question

Скольких способами число 30 можно представить в виде суммы двух чёрных чисел? (Представления, различающиеся порядком слагаемых, считать совпадающими.)

Answer 1

15 раз если не ошибаюсь
2+28
4+26
6+24
8+22
10+20
12+18
14+16
16+14
18+12
20+10ну и т.п

Answer 2

Ways to Represent 30 as the Sum of Two Black Numbers

To represent the number 30 as the sum of two black numbers, we need to find all the possible combinations of two black numbers that add up to 30. The order of the numbers in the sum doesn't matter, so we need to account for combinations where the order of the numbers is different.

According to the search results, the number of ways to represent 30 as the sum of two black numbers is 3. This is based on the following combinations: - 5 + 25 - 10 + 20 - 15 + 15

Therefore, there are 3 ways to represent the number 30 as the sum of two black numbers