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secondary 3 | E Maths
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I’m a bit confused about what the question is actually asking. Does it want me to name absolutely all of the 3 digit positive integers whose digit sum is exactly 9? or... what because that would be a lot of numbers: 126, 135, 144, 153, 162... the list goes on
For reference just in case: The digit sum is the sum of all the individual numbers that make up the integer. For example: The digit sum of 492 is 15 since 4+9+2=15
Date Posted: 4 years ago
Views: 200
Yes, that is what they are asking for
Possible combinations of digits that add up to 9 :
Starting with the largest possible digit as the 1st digit to be chosen,
9 + 0 + 0 → 900
8 + 1 + 0 → 108,180,810,801
7 + 2 + 0 → 207,270,702,720
7 + 1 + 1 → 117,171,711
6 + 3 + 0 → 306,360,603,630
6 + 2 + 1 → 126,162,216,261,612,621
5 + 4 + 0 → 405,450,504,540
5 + 3 + 1 → 135,153,315,351,513,531
5 + 2 + 2 → 225,252,522
4 + 4 + 1 → 144,414,441
4 + 3 + 2 → 234,243,324,342,423,432
3 + 3 + 3 → 333
Starting with the largest possible digit as the 1st digit to be chosen,
9 + 0 + 0 → 900
8 + 1 + 0 → 108,180,810,801
7 + 2 + 0 → 207,270,702,720
7 + 1 + 1 → 117,171,711
6 + 3 + 0 → 306,360,603,630
6 + 2 + 1 → 126,162,216,261,612,621
5 + 4 + 0 → 405,450,504,540
5 + 3 + 1 → 135,153,315,351,513,531
5 + 2 + 2 → 225,252,522
4 + 4 + 1 → 144,414,441
4 + 3 + 2 → 234,243,324,342,423,432
3 + 3 + 3 → 333
See 1 Answer
324
Three digits whole number
All three digits must add up to 9
Three digits whole number
All three digits must add up to 9
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