Question

Сколько существует трёхзначных чисел, сумма цифр которых равна 4? ответы:a)10 б)9 в)8 г)7 д)6

Answer 1

121,211,112,400,220,202,310,301,103,130 10 чисел

Answer 2

Number of Three-Digit Numbers with a Digit Sum of 4

To find the number of three-digit numbers with a digit sum of 4, we can consider all the possible combinations of digits that satisfy this condition.

Approach: We need to find all the combinations of three digits (hundreds, tens, and units place) that add up to 4.

Calculation:

Let's consider the possible combinations: 1. 1 + 1 + 2 = 4 2. 1 + 2 + 1 = 4 3. 2 + 1 + 1 = 4 4. 1 + 3 + 0 = 4 5. 1 + 0 + 3 = 4 6. 0 + 1 + 3 = 4 7. 2 + 0 + 2 = 4 8. 0 + 2 + 2 = 4 9. 3 + 1 + 0 = 4 10. 3 + 0 + 1 = 4

Therefore, there are 10 three-digit numbers with a digit sum of 4.

Conclusion:

The correct answer is a) 10.