How many three digit numbers are there that get 9 as the sum of their digits?
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Of the numbers beginning with 7, only 799 sums to 25, because if either of the other two digits are less than 9, the sum will be less than 25. Show That's one so far. For number beginning with 8, the other two digits must sum to 17. That means they must be 9 and 8. So there are two suitable numbers beginning with 8, namely 889 and 898. That's a total of three so far. Finally, we have numbers beginning with 9. The other two digits must sum to 16, so the candidates are: 9 and 7, or 8 and 8. That gives us three numbers that fit the bill: 997, 979 and 988. How many three digit numbers can be formed using the digits 0 to 9?How many arrangements of 3 digits can be formed from the digits 0 through 9? Summary: In 1000 arrangements 3 digits can be formed from the digits 0 through 9.
How many 3Hence, the required number of numbers =504.
What three numbers make 9?5 + 3 + 1 = 9 eq1 Yes!
What is the digit sum of 9?When adding 9 to itself, we would thus expect the sum of the digits to be 9 as follows: 9 + 9 = 18, (1 + 8 = 9) and 9 + 9 + 9 = 27, (2 + 7 = 9). Let us look at a simple multiplication: 5 × 7 = 35, (3 + 5 = 8).
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