Question

Попробуй записать все двузначные числа, сумма цифр которых равна 15

Answer 1

555
375
357
735
753
537
573
663
366
636
771
177
717

Answer 2

Answer in detail. Try to write down all the two-digit numbers whose digits add up to 15.

The two-digit numbers whose digits add up to 15 are:

- 96: 9 + 6 = 15 - 87: 8 + 7 = 15 - 78: 7 + 8 = 15 - 69: 6 + 9 = 15 - 59: 5 + 9 = 15 - 95: 9 + 5 = 15

There are no other two-digit numbers whose digits add up to 15, because the largest possible sum of two digits is 18 (9 + 9), and the smallest possible sum of two digits is 1 (0 + 1). Therefore, the range of possible sums is from 1 to 18, and 15 is only obtained by the six numbers listed above.